PSA: Managers, leaders, etc...Stop defending your bad employees when your good employees are venting frustrations or bringing up genuine issues.
This is how you create a shitty environment for your workers. This is why you're having good employees quitting or doing bare minimum.
Listen to them, address their concerns, and stop defending bad employees.
If you defend the bad employees you must expect people to emulate their behaviors because if they're doing nothing and getting away with it, then they'll do the same.
Nobody is going to give 100 percent if their peers are getting away with 10 percent.