Not to say this....

Even virtuoso players like Vai.... also spend 8-11 hours practise in a day.. Kirk oso 8 hours ....

But of coz... they can get money of just playing guitar.. which this is oredi their income...

most of us are not full-time musicians like him.. nor we have a stable career like them now..

But I think one day constant 1 hour practise is good enough for most of us..
For me, I set around 2 hours practise in a day.. if really busy oso 1 hour..
But if I am free or boring that day, I may practise up to 5 hours....

whether it is long practise or short practise, most important we must get the correct practise

Practise makes perfect.. .. well, actually "correct practise makes perfect" sounds better