[Perfectlap]

my clutch was springy when it was new. After about 10k miles not as much.
Once the car starts shaking/shuttering on clutch engagement you'll know you should take it in for a check up. But for the good of the expensive flywheel you should probably be proactive and not wait until it gets to that point. And if you do risk the flywheel by waiting a long time to replace the clutch you'll know when the clutch starts slipping.

P.S.
was the previous owner someone familiar with driving a manual transmission? If it was their first car to learn on then even 60K miles could be all she wrote.