I have many experiences with my clients or people whom I had interacted during their commissioning of IVR system, that they give least importance to the scripting as well as voice prompt. Most of the times, they discuss and emphasis on number of simultaneous calls, integration of the IVR with some CRM ( customer resource management) system or some other interesting IVR feature as well as its future expansion as well as maintenance. Nothing wrong for emphasizing on these aspects of IVR system, but after commissioning of the IVR, they have started changing the script as well as voice prompts many times over!

Many of clients have started out with TTS ( Text To Speech ) generated voice prompts and later ended up recording voice prompts by different artists in a studio! I have also seen some call center owner as well as some companies deploying voice recorded in office by some female staff using a PC and MIC, and putting the IVR into production. Invariably, they changed the voice prompts to studio recorded voice prompts from professional artists after one month or so!

While in some cases use of TTS ( Text To Speech) is inevitable or a must ( like retrieving dynamic data from database and playing them out), but there is no reason to use TTS or TTS generated voice prompts fixed menus, numerals as well as fixed names!

I would always advise people to use professionally recorded voice prompts in any IVR in production environment. While use of TTS generated voice prompts during testing and development phase makes sense, but in production, TTS should be avoided. Here are few reasons why one must use professionally recorded voice prompts only :-

1. Voice prompt is the only interface to the caller

In IVR system, voice prompts are the only direct interface with the telephone caller and telephone caller has no means to know about other aspects of the IVR system. A caller to an IVR system is not bothered about the technology behind the IVR system, or use of API ( Application Programming Interface) based on latest web technologies to fetch the required information for the caller at the back end. The caller is just bother about his required information and how quickly he could access it and how easily he could listen and understand without having to press any key to listen again!

2. Professional Voice Prompts gives seriousness to the IVR system

For many call center as well as customer service and support, IVR is the one which picks calls from every caller including the irate and fed-up callers! Professional, clear and pleasant voice ( I avoid using the word female) may have good effect on the caller and it may give indication to him what he may expect from the call! Unprofessional and difficult to understand voice prompts may scare away the caller or make him more non-cooperating irate customer!

3. Voice Prompts may make IVR caller experience pleasant

A clear and pleasant voice with understandable accent as well as pronunciation will surely increase user experience as well as satisfaction of the caller! A person may call to the IVR from a noisy background area and that will compound his problems in understanding IVR voice prompts or menu options if TTS generated machine prompts are used.

A professional voice prompt provider will always make the voice prompt in proper volume, speed, pitch as well as pronunciation which are a must for any production grade IVR system.

So, in order to improve usability and caller satisfaction, one should use services from a professional voice prompt provider, or at least use voice prompts recorded in studio by professional voice over artist.

Like any other computer software, IVR too work inputs of responses provided by the user. Though, a computer application software has widely used input devices like keyboard, mouse, voice, even hand movement, IVR applications have limited, only two types of inputs or responses. One is telephone keypad which has 12 keys and automatic speech recognition!

Another specific difference between a normal computer application software and a IVR software is, IVR can provide the options sequentially in voice while computer application software can software options in various menus, buttons, drop down menu, quick links using related graphics etc. So IVR provides its options or tasks it can perform to a caller in series of voice announcement along with key option to press or word, phrase to speak for choosing the tasks. This is known as IVR menu.

With advent of hosted IVR services, IVR application has become designing of this menu system only, while the integration of CTI hardware with various PBX systems have become standard modules provided by hosted IVR service provider.

Irrespective of direction of call of the IVR ( inbound IVR or outbound IVR), menu starts as soon as the call is picked up. Normally, IVR starts with a “welcome prompt” typically welcoming the caller with greetings and quick short brief about the service, organisation behind the IVR.

IVR menus can be divided into two types depending on how user give commands to IVR application or how user responds to its menu options, DTMF(DualTone Multiple Frequency) or Telephone driven and ASR (Automatic Speech Recognition) driven. Both have advantage and disadvantages and are widely used. ( Click here for more about DTMF driven menu or ASR driven menu)

Apart from above two types of IVR menus, it can also be divided another two types depending on how menu options are generated.

1. Menu options can be recorded using a voice artist in studio and played back.
2. Menu options can be generated using TTS (Text to Speech) converters.

Again, choices in a menu, may be static or dynamic. When the choices in a menu are fixed for the IVR system, than the menu can be called as static menu while if the menu options changes dynamically depending on caller id, time of the day etc., than the menu can be called dynamic. For example:-

In a call center IVR, if a registered customer dials, he may be given different options while an unregistered customer would be presented a different options in the IVR menu.

Many people do not like TTS generated menus as one can make out the difference between human voice and TTS generated voice, specially in India, it has mainly to do with accent of the voice. TTS can be very useful in dynamic menu as well as presenting data retrieved from database where playing recorded voice may not be possible all the time.

Usability of an IVR depends mainly on the design of IVR menu. For more about usability one may check this : Usability of IVR systems.

An IVR user is interacts with IVR through it menu only. So it is very important to design IVR menu which is easily understandable to first time callers. Previously people used Visio like tools to design IVR menu. But now a days, almost all IVR development tools come with powerful, feature rich visual IVR menu designer giving DYI(Do It Yourself) feature for IVR customers.

What is IVR customisation ?
Normally, an IVR application is designed and developed as per requirement of the customer by IVR companies. But they have ready-made modules tested and readily available for quick development. Normally, the modules like, telephone interface, ring detection, caller ID detection, database connectivity etc. are always readily available. Also many people use RAD tools for IVR customization where they simply implement call flow required by the customer. So IVR customising can be described as implementing call flow of the IVR application as desired by customer using existing IVR related software modules.

In fact, after RAD (Rapid Application Development) tools have been introduced, IVR development have become just IVR customisation. Many IVR functionality, modules are available in RAD tools ready-to-be-used. It is not easy to develop an IVR application from scratch, as it involves auxiliary knowledge and experience about telecommunication switches, telecommunication standards and protocols, speech recognition, TTS.

While RAD tools are easy and quickest way to developed customised IVR application, but it may not suitable for IVR customisation which needs to interact with existing business processes or existing software which generate various data to be provided by the IVR. For example weather update, complaint ticket generation, complaint status update etc. Apart from these kind of complex and very sophisticated IVR systems, RAD tools are excellent development or customisation tools for IVR solutions.

One important aspect which many people overlook is writing script of voice prompts and recording of voice prompts professionally. IVR systems are to be deployed to be used by normal people for availing services, solutions from it. IVR system interacts with its user ( caller to the IVR) through voice prompts. Any mistake in voice prompts may render the IVR useless. For example, if the voice prompts announces, “to know your complaint status, press 1, or press any key to end the call.” Now imagine if IVR is coded to recognize 1 for disconnecting the call and any other key for asking further information to retrieve complaint status!

So, while customising IVR application, one must write script for voice prompts and record them with professional voice artists. Without this, IVR system may have the best of the hardware and most well coded software, still IVR system will not be useful to its intended users.

While customising an IVR application, one should think about future enhancements. Many times, one finds out that existing codes can not be used for enhanced services, features and everything needs to be done from scratch. This not only delays the process of upgrading IVR systems, also it become costlier.

While integrating with third party application or software, direct interaction with their database should be avoided. If you do so, any changes made by them would require you to make changes in your code too. So I think HTTP URL is a very good approach where you send few parameters for exchanging data from third party application. This will ensure that your IVR code need not be changed even if third party database is changed.

VUI ( Voice User Interface) is the call flow of IVR system. Usability of IVR is dependent on the VUI. So it is desirable that considerable amount of time be devoted in designing, testing and documenting VUI of IVR system before actually developing IVR system.

Here are few simple VUI design guidelines of tips I have thought of :

1. Identify specific purpose of IVR system
First step towards designing VUI should be the question, why would a caller call the IVR system and how quickly efficiently IVR should reply to his “why”. If the purpose of an IVR system is to record customer complaint, allow customer to lodge their complaint in the first menu itself. IVR should not try to act very smart or human by asking intelligent questions and get the caller answer before it actually is able to lodge the complaint. The other way is to allow the caller lodge the complaint, provide him complaint ticket and then ask few polite questions about details of the his complaint an which is completely optional. IVR system should stick to its specific purpose in its operation.

2. Maximum 3 Levels of menu
Stick to maximum 3 levels of menus before caller gets his desired information after calling a IVR system. A caller should not be “interviewed” or put through “set of question answer session” till he gets the desired information. In many IVR system, it is observed that, trying to be smart, caller is put through set of questions, many irrelevant options before actually providing the information required by the caller. So, golden rule should be, provide maximum 3 levels of menu, before a caller is answered or provided the final information.

3. Provide Shortcuts as per usage
IVR system should have in-built MIS (Management Information System) to enable finding out the most used menus and information. Depending on the usage, shortcut should be provided to access the widely used menus quickly. Many repeat caller will not like to go through the same menu and having to choose same options before his desired menu options. Even a first time caller may like to use the shortcut once the shortcut is explained.

4. Top Level Menu options
By top Level Menu options, I mean the menu options provided to caller as soon as his call is answered. This is the menu which is to be designed very carefully and success of IVR system may depend on this menu to a large extent. This menu should not be long list of options, but few main specific purposes of the IVR system. And this menu should be changed as per usage statistics. For example, if the 4th option here has less usage than 3rd option of the second level option of 1st top level option, than most probably, it is time to bring the second level option to top level menu. If the IVR system is a call center and human agent is available, then I strongly suggest that option should be given to caller in Top Level menu to speak to a human agent.

5. Voice prompts
Voice scripts should be simple English or the language the IVR is using. The language should be really simple and easy to understand, without any grammatical errors. It should be spoken as if you are speaking in daily conversation with regular pauses. A good menu design may look totally ridiculous if proper scripting and voice prompts are not used.

There are five VUI design tips I have been using in all my IVR works. VUI is a must for IVR usability.