I guess that is the motivation for people trying to do things themselves instead of hiring a professional - that is, someone who does it all the time. I was guilty of that with the tiles on my verandah at home. I laid them and nearly broke my back in the process. I never wanted to look at another tile in my life by the time I finished. But I thought I did a pretty good job.
Then the other day we had a builder and and architect at our house, and they both commented on the tiles. What they said though was that they couldn't believe how bad they were.