I agree and understand they should be given a chance to fix IF these were isolated instances. This has almost became a UPS culture issue. It is managements culture in a lot of facilities that if they need 20 mins off a shifts time to meet their numbers to just go in a get that 20 mins, or at least that is how it feels to a lot of people. This is where it appears a lot of the variances come from. In the past I have had sups admit to me that they saw so-and-so changing employees times to meet their numbers. I don't normally have issues with the accidental screwup on time (unless it is repetitive, which i will explain in a minute) as it can happen, but it is the intential aspect that needs to disappear.
That being said, there is a point even on the accidental aspect where enough is enough. for example, I took the same option day last year 4 times over about a 4 month period and still got paid out for it when I had a medical leave. 1st time under pt sup #1, ok no problem, 2nd time under pt sup #1, hmmmm, 3rd time under pt sup #2, wth (I actually trust this one, one of the few), 4th time under pt sup #2, wtf is going on, reply "I swear I put it in the computer", to FT sup " i want to know why in the hell i can't get paid for this day", never got a reason but did eventually get the money. It wasn't so much the money as the frustration. But I guess I got extra days off right?