[danieltillett]

I think you are self-aware enough to know why you were fired so I won't comment more on this.

The reason why firing the person who comes in first and leaves last is so hard is because of the signal it sends to other employees. If the employee everyone sees working the hardest gets fired what does this mean for everyone else - are they about to get fired too? The only way you can get fired with this strategy is if you goof off at work. Keep your head down and work like crazy (or at least appear to work like crazy) and you will be fine.