The GANSO website that I mentioned earlier has bi-weekly reports of various dangerous things that happened in Gaza.
One interesting thing that they mention in these reports are the number of rockets and mortars that either explode prematurely or that fall short in Gaza.
According to their figures, over the past month, Gaza terror groups fired 19 rockets (that these NGO's call "homemade") and 14 mortars towards Israel. Out of those, 8 rockets and 8 mortars fell short or exploded prematurely.
That's a 42% failure rate for rockets, and 57% failure rate for mortars.
No wonder Hamas and their NGO partners want to import more raw materials into Gaza. The quality of weapon components they are getting from the tunnels is abysmal!