Quoted from vid1900:
A tip for the future, Bondo is too fragile for doing durable repairs anywhere near a corner of a cabinet.
One hit, and a big chunk comes off.
Use Bondo FIBERGLASS RESIN instead, that is made for structural repairs, like the edges/corners of a cabinet.
Regular Bondo is fine for filling scratches, holes and gouges in cabinets - as long as they are not near the edges.
Personally I've been lovin' on this stuff!