Its my opinion,
Reasons of not getting 90+ in cs
- There was no need to get 90+ marks when you are getting rank 1 in 80s and top 200 are in like 70s range and last year in 2018 you were in top 500 if you get 55+ out of 100. so if you are in top 200 you are getting same college as air 1 or an equivalent college so that's why nobody thinks of getting 90+.
- second thing is gate cs paper is one of the conceptual papers so scoring 90+ requires a lot of accuracy and brainwork since there is time bound. other papers in which there are 90+ score it is because most of the paper is formula based and less conceptual as compared to computer science. if one is able to remember formulaes and has accuracy in calculation then he/she can easily get 60+ and with hard work he/she can push himself/herself to 90+. I am not saying that other papers are easy.
- third thing due to which student get 90+ is competition. you have a high level of pressure to get as much marks as possible because someone is there who is preparing harder than you to get more marks. There are lot of CS jobs available and after mtech placement of cs is better than most of the branches so people are less serious for getting 90+ coz they have backup options available whereas other branches mainly compete for psu as core jobs are less in other branches as compared to cs and most of them are less interested in doing mtech due to poor placement as compared to cs branch.
how to get 90+
working hard is the only option to get 90+. for me working hard means that you should be able to attain a level such that whatever question I give you related to gate syllabus you should be able to give me the answer within 3 to 10 minutes.
ways to achieve 90+
Ways to achieve it is by practicing good quality of new questions and learning each and every concept thoroughly. whenever some asks you some concept you should be able to visualize what is happening in the question. if that is not happening then you are weak in that concept.
Nowadays competition is increasing in cs , so you can expect someone to get 90+ in the coming 4 to 5 years.