[interdrift]

You got two options :

1.Give him a better solution and prove that it can be done better 2.Let him drown and drag you in too.

[JoeAltmaier]

Actually, at a paid job, you can't really redo your coworkers tasks and also get your own done. Not being paid to do that.

[interdrift]

What you are saying is true, but it's still very relative since it depends on the situation you are in.