Bathtub refinishing terminology gets confusing. In it's simplest definition it is the process of applying a new finish to the bathtub. Which also works of Porcelain, fiberglass, acrylic, cultured marble and plastic surfaces.
The problem with the definition is it fails to tell you how the new finish should be applied and what that finish should be comprised of. I have been in the bathtub refinishing Industry since my senior year of high school 1991. I went full time with my business in 1992 and I have seen the craziest things put onto a bathtub and the unbelievable reactions of people when those paints failed and peeled. (The video below shows the failure of a bathtub after less than 1 month)
The problem is the fact that this was actually considered bathtub refinishing but in all honesty it was bathtub painting and the two are completely different processes and materials. Bathtub painting can be accomplished with inferior coatings such as Latex paint, Epoxy paint, Acrylic Urethane paint and Lacquer paint just to name a few of the ones I have seen!
Most consumers don't know that the Professional Bathtub Refinishing Association has a set of guidelines when it comes to refinishing and very few so called Dallas bathtub pros follow.
First, they do not recommend using any type of paint. In fact it is a synergistic process that involves a combination of:
Dallas Bathtub Pros
Integrating the new surface into the old making the surface a permanent part of the fixture.