I am prepping to paint my house. The previous paint job wasn't that long ago, but the work was kind of sloppy. There are several localized areas where the paint is chipping or bubbling. Obviously I will need to strip, sand, and prime these areas. However, there are also lots of areas that look perfectly fine, but the paint can easily be stripped away in large, rubbery sheets, with just a simple scraper and no chemical or heat treatment whatsoever, leaving the primer underneath intact. I am concerned that this is indicative of the paint not having bonded properly to the primer (which has a very slick, smooth texture), and that if I do not strip this paint away and simply paint over the top of it, the new coat won't last as long. But I'd like to know if that is really the case before I undertake all the work, or if that is possibly just normal behavior that I don't need to worry about.