Halloween yard props fail at the stem, not the face.

If your tombstone or pumpkin snaps while you carry it outside, it is almost never the STL. It is a 2-wall shell with 10% infill and no brim, printed on a cold plate in a garage.

What I run for outdoor FDM props on a hobby printer:

• 0.2 mm layer height

• 3 walls

• 15–20% gyroid infill

• 8 mm brim

• PETG if it will sit in sun. PLA is fine for a weekend, then it warps.

Dry the filament. A wet roll will look like a bad model.

Questions about a specific fail belong in a photo plus your printer and filament. That is faster than guessing from a description.