My company lost the deal because I sabotaged it so that I wouldn't have to work late.
Why don't you want to work late?
I'd rather stay home with my family.
It is wrong to lose a job on purpose that effects other people. You should tell them the truth or try to find a new job.
I might do it again next time.
You'll eventually get caught, and then fired. Your business expects you to work as hard as possible and this is the exact opposite of that.