There's basically only two ways to blow a sub, thermally (too much current through the coils, they over heat and melt) or mechanically (sub is over-excurted beyond its motor and/or suspension limit, causing it to bottom out).
Thermal issues would be caused by too much input power to the speaker, a heavily clipped signal, and/or something that hurts the sub's ability to cool itself (mounting pole vent too close to rear wall for example). Thermal problems are generally caused by incorrect gain settings, bass boost, or both.
Mechanically you can only over excurt the sub by giving it too much power, building the box incorrectly (too big, too much prt area, etc) or driving the signal down below tuning in vented applications where the sub unloads.
Everything else is voodoo.