If I clear CAT but not PI and GD my clearing CAT is waste

See all good Bschools have a practice of GD and PI some have started Wat-Pi process as well. So yes if Cat is cleared with a good percentile and you cannot perform well in the further processes it can go as a waste.
Although you might still end up in a small college which is below your league.
So it is better to start practicing for it.
Because noone was good at it first all worked hard and reached that place.
All the Best.
SMIT-IIM-AMRITSAR-PGP/04

Hi Aspirant,
After CAT,every college releases it's cutoff.
If you score above that,you will be called for GD/PI.
If you clear them,you will be eligible for the admission in that college.
Hope this helps.