App note: Through-Hole versus SMD components

App note from Vishay on the advantages of using Through-Hole mounting. Link here (PDF)

Most electronic gadgets are designed to interface with humans, and we humans are very abusive to most electronic devices. We drop them, poke them, open and close them, and in general feed stuff into and out of them.

It is well understood that a through-hole connection to the PCB is mechanically stronger than most surface-mount connections. By comparison, the strength of the bond that holds a surface-mount component to the PCB is limited to the strength of the solder joint that holds it to the surface of the laminate. As parts get smaller, so does the amount of solder and thus the strength of the bond.