Joining bonus improves retention.

What's stopping HRs from giving out joining bonus?

Psychology clearly says people want to minimise loss more than maximising gain. They would even switch to a new org without getting their variable payout. But paying back the joining bonus sucks. You have to pay it out of your pocket (psychologically). This makes the new joiners to push boundaries and stay till the threshold time. I have seen a lot of such cases where people quit without variable pay but stick for 1 year in toxic env just not to payback joining bonus.

Thoughts?