I used to work in a sales job that paid just above minimum wage but a sales commission bonus that ranged from £400-£1200 a month. I quit the job a few months in as the workplace was toxic ( encouraged to sell insurance illegally to elderly and vulnerable customers, and to trick them into purchasing items they didn't need).
The clause in the contract was that commission is paid out in arrears and will not be paid out if you quit, even if you provide notice. This basically traps employees as they are so reliant on the commission ( which makes up a significant proportion of their compensation) that they will not quit, and corporate companies acknowledge this by making working conditions worse and knowing they are unlikely to leave.
It also resulted in me losing around £800 in bonus that I had earnt, but I was a naive teenager. The way that I now look at it is I was always going to lose any bonus that I had earnt, because I would eventually leave the company. The bonus is retained by the company, who are multi billion pound firms.
This is a common practice and is legally acceptable, as companies lobby government to ensure rules are designed to trap and control workers. I am going to shitpost them online to see if thee is any way I can claim any of my commission as I feel that it is an unreasonable clause, but I know it is legally watertight.