Usually you don't get a raise because you deserve it, you get it because the company believes keeping you will result in a more positive financial outcome in the next few quarters than replacing you.

Plenty of companies give their engineers a chance to pay their tech debt, whether it is bad code, bad infra decisions, etc. If you don't believe some engineer is capable of paying their tech debt, you may as well let them go. Or not give them a raise and hope they leave, which at most places is much cheaper.