Peeling paint occurs when cracked paint begins coming loose from the wall or coming away from the original surface.
Peeling is likely to occur if a paint surface has not been properly prepped. The issue usually occurs if the correct primer has not been applied. It also regularly happens if the paint is of lower quality and does not have the right flexibility or adhesion, or if paint has been over-thinned and spread to thin. Peeling is also frequently seen on areas that are damp, or have a lot of moisture.
Make sure to use a high-quality primer and paint, and to ensure that your painting surface is properly dried and prepped. Make sure paint is applied generously. Also, ensure to regularly check for cracked paint lines or peels in order to catch peeling paint at its earliest stages.
In order to paint over peeling paint, you must first remove all peeling paint using a scraper, sander, or wire brush. Once all peeling paint has been removed, dust the area, apply an adhesive primer and paint as usual.