If there are major forces coming across the part, it is likely to delaminate at some point, however if you can construct the part so that forces are in line with the print planes rather than across it (peeing the layers) it is very possible to print strong and durable parts. Keep in mind that 3D printed parts are about 5 times weaker than their injection molded counterparts, so design wall thicknesses and more internal structural features accordingly. Ditto advice on outdoor use as CAardvark, I have a few parts outside for 3 years now as a test, the PLA remains fine!