I am painting the walls in my garage and places the plaster seems to be flaking off under my roller in places at the present time I have been stpping then scrapping the paint and plaster off in that area and repainting with a brush which seems to be working and I plan to put a second coat of paint over the complete wall but my question is what did I do wrong, what caused the failure I still have another side to paint and do not want to have same problem, I am using Sherman Williams Paint.
Thanks for your help.