I've heard this quite a bit from web firms that have an old, ugly, outdated website showcasing their work. The message being "we are too busy making our clients' websites great that we have no time to invest in our own." Being a mechanic in an ex-life, however, I would like to put this myth to rest and take away the excuse for not enjoying your job.
When I was working as a mechanic, I saw two distinct sets of workers: those who decided on this career because they could make a paycheck, and those that truly loved cars. I also saw a very distinct way these mechanics worked.