In some cases, the best method for assembling parts is obvious. In others, the choice is less distinct.
So how would you assemble a sheet-metal box to house electrical components? That’s easy, you say. Plenty of mechanical methods would work: screws, rivets, snap-fits, even toy tabs. Yet, other engineers might prefer spot welding, and at least one manufacturer of such enclosures uses adhesives. Perhaps it’s not such an easy decision after all.