Another reason television is not more suitable than book because when children learn through television then their focus will be on audio visual presentation; not in learning. Whereas if they follow books then they focus on books and the lessons it offers.
It is often heard that many children watch TV for a long hours and that is detrimental for their health. Television programs are addictive and many children do not concentrate on other important things like study or outdoor activity when they become addicted to watching TV programs.