Stemper
One who makes foolish decisions. A useless map-reader. A driver of excessive speed on an unsafe road. One who fails in many areas of life, try as he might. One who is prepared to stick to their guns... even though they know they are wrong.
As in a parental warning...
'Mind him... He's a bit of a stemper'.
Or
When hitting one's thumb with a large type hammer one may inoffensively shout..... "STEMPER!"
'Mind him... He's a bit of a stemper'.
Or
When hitting one's thumb with a large type hammer one may inoffensively shout..... "STEMPER!"