You have to agree we Indians are one of the best non-native speakers of English language. In my opinion, the measure is based on the probability that the other party can understand irrespective of where he is from and if he is a native speaker. For example, Indian accent is such that it stresses most of the syllables which make them easier to understand of course it is sometimes very very different than how natives speakers (British/American) would say. In this era, English is definitely not just the way the English (people of from England ? ) speak. I think the way Indians speak is far more understandable than they way they speak in most Europian countries minus Britain, after Brexit I can just say most countries in the europian union. Probably that is the reason why we have very good relationship with USA from IT/Software industry perspective.

Having said that, within India itself there are so many ways people speak English depending on their first language. I am sure this is the case in USA and Britain also given that the accent in southern states of USA speaks bit differently than the north-eastern ones. Here in India most of the times you can very accurately tell the where the person is from when you hear them speaking English. For example, the same word "bus" is spoken by a person from Bengal as "baas" but an Odia guys would speak as "boss". Probably the correct pronunciation is somewhere between these. Same for the work "bug", "cup" etc. The sound of "u" that is used in the word bus does not exist in any of the two languages so they just map it to one of the closest vowels.

If you go to the western India like Gujarat, you may hear the word "Snack" as "Snake" and "wrap" as "rape".

South India (for me the state of Andhra Pradesh and south), its a totally different ball game. I tend to generalise because it all look the same for me. I am sure, same is the case from the perspective of a person from the south about the north Indian states. If you are an Indian probably its a piece of cake for you to distinguish people from south India from their English accent, sometimes from the tone itself. Speaking of specific words you may hear the word "Fixed" as "Fix-ed", "against" as "egg-nest", "environment" as "en-vee-ron-ment". These differences becomes more prominent, more the south you go in India. The way words starting with "H" is pronouces is also has a pattern i.e. "Honest" is spoken as "hon-est" not "on-est". Same for "Honour" , people may say "hon-or" not "on-or". Putting all these deviations of English pronounciation aside I must say people in south are better in English than other states becaise lack of familiarity with Hindi. English is the only fall back language if you are talking to someone from another state. If I can take the liberty of steriotyping, they learn English well because ultmate goal is to settle in USA :)

Now lets talk about North !

Most of state speak Hindi. When you hear English you may observ the letter "W" and "V" used interchangably, in fact swapped most of the times. "Venus" is spoken as "Winus" and "Wicket" is spoken as Viket". In fact I have friends who in the chat write "ve" instead of "We",  not how it is a short hand because both are two word letters. Its just how they think it should sound like I guess :)

Its very hard to realise this mistake for a native Hindi speaker but no one really teaches the specifics of pronouciation of the letter "V" i.e. the upper theeth should touch lower lips not just "we, I think the culprit is the hindi letter "व" (wo), which people end up mapping the letter V to. However in Bengal and Odisha people map it to the closest sound "" (ভ in Bangla and ଭ in Odia) because there is no equivalent of Hindi "व". Some some people may end up saying "Bhinus" for "Venus" and "Bherification" for "verification". 

The exclusivity of some sounds to a specific language plays an important role when we pronounce names. We can to literal translation of words to our own language but can't do the same for name. One has to pronouce the names as it is given to the person in his language because that is the point of giving the name, it does not have to have a meaning its just to indentify & address people. Some people just say the name the way they write in English but I believe thats not a good idea. They write the name English in a different way because there is usually no sound available in English alphabet  to depict the sounds that contitute the name. And name is spoken first and then written so does not matter how the name is written in English letters , one must pronouce it the way the person himlef does. The sound takes priority. For example if the name is written like "Jose" I can't say it like "Jo-se" just because I am speaking in English, it must not be translated , it has to be keept same as original ("Ho-se") no matter what language you are speaking.

Ambiguity can also asrise becaise same english letter can have two sounds. E.g. if you see the name "Serge", it could be "ser-ge" or "ser-je" , I have also heard "surge".

 Well I can't blame any of them, if you don't have an equivalent sound of a letter from foreign language and not taught how to make that sound, there is no option other than mapping to the closest sound from your mother toung. However some people can actually adapt very quickly and speak in the foreign sound some just can't which gives rise to stereitypes. Hey that also gives a lot of content for humour :)

While we can make fun of each other we have to understand the variations would exists no matter what. It exists when people from europe and south asia as well. India is such a diverse country the variation exists even within the state for a same regional language. The only goal should be to speak such a way that the other person can understand. You could be travelling or seeking a job and there could be very small window where you can express yourself without putting a lot of cognitive load on the other person. To take full advantage of that its never too late to step back and take a look at the words again how it could be spoken in a more neutral way without any accent. Again it does not have to be phony to impress someone or mimic a native speaker from America or Britain, it just have to be standard enough to be understood by the other person without having to repeat.

Here are some videos, book and DVDs from Dr. Ranbir Sinha, give it a try if you think the way you speak needs improvement.

  • Modern Spoken English for Science Students Textbook + Timed Audio CD

    UPDATE: I also forgot to mention that it could be little annoying and difficult to understand (not just accent, but also if your colleague is unable to form a simple sentence to convey his thought )  if you are not speaking words the way most fluent speakers speak. It does not just apply to Indian English speakers, but also the French and Germans. Probably the key thing is to take your time, speak less and slowly and make sure the other party understands it. Meetings in engineering jobs can go unproductive if ideas and solutions can not be explained properly. There is another book that Dr Sinha has written I would recommend for scientists and engineers. There are fancier and costlier English speaking courses in the market but this is directly based out of personal and professional industry experience, not only from academics. Give it a try.