Dead pitches is main reason for this. These dust beds are prepared for spinners and batsman. That why India has a long line of batsmen but not a single speciality fast bowler except Zaheer. Secondly Indian craze for batsmen. If bowler take 5-6 wickets he gets only Man of the Man award, but if a batsman hit some sixes, he become hero of whole nation. Everyone wants to be like Sehwag, Yuvraj, Sachin, Dhoni. Very few players follow Kapil, Srinath or Zaheer.

Tradition, climate, training ground and training coach, short body, lack of encouragement for fast bowlers earlier, over importance for spinners all contribute to this. Those started as fast soon becomes medium pace as a result of susceptibility to injury. The desire to last longer in the field also is there. To maintain speed and accuracy is rather difficult.

First and foremost the physique as well as the proper training method and may be climatic conditions some time may adversely affect. The last but not the least the corruption at the higest level, even though we may be the richest board in the entire world, but due to some reason or the other reason we could not provide the facilities and that is a great tragedy. due to this reason we could not produce the fast bowler who can bowl at the speed of 150 or more .

Wait for another 5-10 years

Players , you find are all self-made. India have no contributions in any form. No pitch, academy & trainers in that sense. Sporadic TRAINING CENTRES , floated by a few ex-cricketers alone will not help. Those are all money-earning centres , to be extracted from the aspiring parents.

Following factors :-

high ambient temp
more air pollution
lack of proper training in school level (including food habit )
lack of play grounds
expensive training