Pretty poorly worded and confusing. Giving it a go, it seems to be saying that you don't get a bonus if you're late 3 or more times, regardless of the total accumulated late time. If you're late once or twice, you can still get a bonus if the total late time added together combines to 2 hours or less.
Cure period usually means the time to correct something. This may have something to do with the definition of "late". If you're 5 minutes late, does that count? 10 minutes? If you're late one day, can you make it up by being early another day? You'd need to look in the contract elsewhere for context on this.