Once a cheat always a cheat? What's everyone's opinion

First you gotta under why they cheated. Most people, infact i think you could say everyone who cheats, DO NOT INTEND TO GET CAUGHT. They do it because they think they can get away. I mean, would you throw away a 5 year relationship for a quick bang? Most people wouldn't. But you factor in that get-out-jail free card where you could do anything and not get caught? a lot more heads would turn. I'm not saying it's forgivable, or that you should hang on to a cheat, heck my ex wife cheated on me with her colleague, found them when i went to pick her up at her office. But I could understand why she thought she could get away with it. She's there 8-9 hours a day, i'm totally on the other side of the country working, bam. Victimless crime, not so much. If you can understand why and who they cheated with maybe you might have a better context to make a call on it. But if you don't, sucks like hell yo.