Income tax return

No it is not compulsory if you are below basic exemption

NO but in some cases you have to file that are :
1. If you pay 50K as electricity bill
2. own an immovable property
3. own or taken on lease motor vehicle other than 2 wheeler
4. paid club membership fee more than 25000
5. own or beneficial owner of asste outside india

it is better to file i.t return

....if any tds deducted u can get it refunded.....it is always preferrable to file...coz it may save in emergency situation s....

If you pay 50K as electricity bill
2. own an immovable property 
3. own or taken on lease motor vehicle other than 2 wheeler 
4. paid club membership fee more than 25000
5. own or beneficial owner of asste outside india 

these conditions have been removed...

Short answer : NO. But it totally depends on case to case.

if ur taxable income is less than prescribed limits now 250 k later in future sone other figure then submit in case u have only bank interest then form 15 G OR H .
if u have capital gains taxable under special rates then whatever small value u have to paytax and file return.
if u dont file return thinking ur incone is not taxable be cause it is less than invone tax limits FINE...
ONLY POINT TO NOTE IS ITO MUST ALSO SHARE UR VIEW. IN CASE HE ISSUES NOTICE U HAVE TO PROVE UR POINT WITH SOLID EVIDENCE