It stands to reason that they have expended much of the newer arsenal, and are now more reliant on limited shelf life weaponry as TINSC explains below.
From my buddy TINSC:
Some of the civilian targets hit as of late MAY have been hit by HAMAS rockets. The standing rationale is that HAMAS wants to generate civilian casualties and blame them on Israel.
While it is a habit for HAMAS to blame everything on Israel, I have another theory. These civilian casualties are being caused by HAMAS but they are not deliberate. My theory is that HAMAS has used up so much of its newer and better ordinance that they are using their older and less-reliable ordinance. This older ordinance fizzles out in flight and hits targets in Gaza.
So the Gaza civilian casualties are not caused by Israel but they are not being caused by a deliberate act by HAMAS. HAMAS has depleted its weapons stockpile to the extent that HAMAS is using their less reliable ordinance. It is this less reliable ordinance that is landing on civilian targets in Gaza.
As we all know, the Jews get blamed no matter what. I just question whether HAMAS is deliberately targeting their own civilians.
“We can see that the volume of long and medium range rocket fire is gradually decreasing, and more and more fire is falling within Gaza, directed at IDF forces. Much of this fire is falling in Palestinian territories,” the officer said. He explained the change in the pattern of fire with IDF forces activity in the Gaza Strip, as well as, aerial activity against rocket launching sites, and Hamas’ intention to manage their ammunition for prolonged combat. According to IAF data over 4,000 targets were attacked, nearly four times more than were attacked by the IAF during Operation Pillar of Defense.