Why are tractor operated cotton pickers not successful in India?

I think size and money matter for Indian farmers. It could be possible to make it more popular by making low cost machine as well smaller in size. Other reason may be availability of labour at cheaper rate.

Reason for low cost machine is right but the ripening of cotton balls in India required at a time. Picking needed at least 2-3 times so it is not feasible with these varieties which we are using.

New Holland plans cotton picker ‘designed for India’

I'm in accordance with Mr.Paten and the NewHolland director's artcile. Furthermore, I well know the indian farm and farmers, and they are (in general) not very able to drive a complex machine that cost a lot of money. For these reasons only when the average ability of operator increase and price of machines go down, mechanization of cotton (or other crops) will be a reality...

Indian cotton varieties have problem of synchronised maturity, we need atleast 2-3 picking of cotton because of unsynchronised maturity, Tractor operated Cotton harvester are not selective, hence cannot work in indian condition, also for tractor mounted harvesting we need shredder, which are also not developed for indian varieties.  in Indian situation as of now Hand operated and Knapsap cotton picker are possible to introduce.

Picking of cotton goes over several months, because of the non synchronous nature of cotton. This is because farmers cultivate the long duration cotton hybrids. Further, the cotton pickers developed (JD, NH) are more suited for high density planting systems and synchronous boll opening. It is a one time picking job in all the other countries where cotton is cultivated. Moreover, these machines are exorbitant for an Indian farmer. Hand picked cotton is cleaner than the machine picked cotton and there is no need for an additional cleaning process. 

An attempt is being made to develop a selective type cotton picking machine at our university but needs an industry support. Please suggest the name of industry who will support in developing picker. Most of the work has been done but still requires industry support.

India is still not ready for mechanical cotton harvesting. It need lot of changes in cultivation practices i.e. row spacing, plant growth regulator, defoiler and ball opener.

Thanks to all for interacting on cotton picker.

Maybe the cotton variety is inadequate with a cotton picker machine.