Cause: the surface had pre-existing flakey paint/varnish.
Paint is only as strong as the surface you are painting. Ensure you sand the finish before painting to remove any loose paint or varnish.
Cracks in Finish:
Cause: The surface is flexible or soft.
Soft substrates like bamboo, cane, cork etc may be softer than the paint, causing the paint to stretch beyond its limit.
Cause: Painting over oil based paint.
Painting an acrylic based paint over an oil based paint will cause the surface to unpredictably crack.
Cause: Dirt, wax, grease or oil on surface.
Ensure you clean the surface well before painting. Use a detergent such as sugar soap and remember to rinse off the residue.
Cause: Ultra smooth surface.
Use a high adhesion primer when painting glass, ceramic, laminate, formica, pvc plastic or high-gloss surfaces to prevent peeling.
Cause: Environmental factors.
High humidity or condensation may trap moisture layers between the coats causing it to peel.
Chipping or Scratching Off:
Cause: Sanding dust residue.
Each time you sand, clean off all the sanding dust before painting.
Cause: Too much paint.
Too many layers of paint will cause the surface to become soft, and prevent it from curing properly.
Cause: Not yet cured.
Allow the paint to full cure before using the furniture.
Blistering or Bubbling:
Both the surface and equipment (brushes, stir-sticks etc) need to be clean to avoid any possible contamination to the paint.
Cause: Damp project.
If your project is damp, especially internal dampness, this will cause moisture to evaporate through the paint layers.