Why Magazine Disconnect?

When playing with C&R guns I've noticed a few Browning designs which initially did not have a magazine disconnect and grew one in later production.

I've long wondered why and there doesn't seem to be a definitive, or authoritative answer.

I speculate that some people got shot with the, then, new fangled semi-automatic firearms because they thought that taking the magazine out completely unloaded the pistol.

The addition of magazine disconnects to existing designs happens almost all at once in the early 1920's.

Magazine disconnects aren't really common, but they aren't uncommon either.

Most of the time they appear on guns destined for military or police use, so I think that their presence was mandated by the buyer's request for proposals.

Other times, I am not so sure.  S&W's 39/59 series of guns likely has the disconnect from being proposals to the Army, but there was a lot of changing done to the X100 to make the 39, and omitting the disconnect would have been a simplification if they'd wanted to do it.  I think that someone in 1950's S&W liked the feature and included it.  Then it became a distinctive feature of the line-up and remained until the third generation ended production in the very early 21st century.

California's absolutely idiotic laws have driven its inclusion in several modern designs.

I'm on the dislike of the feature side of things.  I tend to avoid designs with it or remove it from them where I can.