Hi, I got the task "lose all your happiness", but it's nearly impossible: once your happinness is too low, you can't do any more happiness losing task, and thus, except if you are very lucky with the number, you have 1 or so in happiness at the end.
I would suggest to either make that the task is successful if you are under the minimum value for stat reducing task or that you can do a task reducing a little a stat if you are not at 0