I'm speaking of regular, hourly-based or salary jobs that are not tip or commission-based. Given that no one is perfect, I'd look upon that policy as a scam for my employer to ensure that I was never given the pay I was promised when I was hired. It's a tactic to screw over the employee and no doubt also designed to ensure high employee turnover so that raises (and therefore increased employee costs) are highly unlikely. And I'd be leaving asap.
However, when I worked on commission, if I screwed up, then no, of course, I didn't get my commission. The rules of commission-based income are entirely different than the hourly wage. Moreover, a commission-based income is never promised to an employee; the pay is determined by a number of factors including how well I did my job, but also including the weather (how many people were out shopping), time of year, the economy, the competition having sales, etc. Some weeks I made a lot of money; other weeks I didn't. That's the way it goes when you work on commission -- you can get incredible highs, but you also take the risk of incredible lows as well. If one wants a more guaranteed income, then commission work is not the way to go.
ETA: And of course, if I screwed up enough at any job, I'd be fired.