This is a problem with M2's
The shell magazine retainer does not allow you to release shells from the magazine manually, as it should, unless you have incredibly strong fingers. That is no good and it is true of every M2 I have handled or shot.
The M1's did not have this problem, and the Ultra Light does not either. I have all three types of guns.
Why would having to live-cycle rounds be a problem? Because you should be able to remove shells quickly and as safely as possible, and this limitation compromises that ability.
I unloaded my model #37 pump for years, which has a similiar type of magazine retainer, in about 3 seconds, by pushing with my finger on the retainer.
At first I thought this is a design flaw, but now I think the Benelli engineers wanted to insure that shells would not kick out of the magazine prematurely for whatever reason. I am not a pro gunsmith, but I imagine some judicious filing would tune the retainer to allow manual unloading. There's probably drawbacks (aside from warranty issues) with that idea...
So, you have to cycle shells through the chamber to get them out of the gun.
Bird Guns Will Travel