BGAs are nearly impossible to hand solder. You can theoretically do it by flipping them upside down and soldering individual wires to each ball, but this is very difficult, unreliable, and harms signal integrity. It&#x27;s completely unsuitable for production and even for prototyping it&#x27;s basically never done.<p>Through hole components are commonly hand placed or hand soldered because there are only a few on the board, not enough to make machine placement&#x2F;wave soldering cost effective. Additionally, some through hole components have shapes that make machine placement difficult.