In the e-myth book (other comment) that guy says the entrepreneur should do what they are good at doing and what they enjoy doing.
And hire everything else out.
Still, lets say you can make $100/hour coding.
Do you build yourself the table that you want or do you go try to find a table that is acceptable and pre-built?
The other end of this equation is that you do have 24 hours each day. If you have time burning, and no houses to fix or fires to put out, well than, hobby time.