Loki’s wants to take down the Avengers and the S.H.I.E.L.D. helicarrier, to disable the two greatest threats to his invading forces. To accomplish this, he lets himself get captured and the glaive taken away from him, knowing Banner would study it, fall prey to one of its terrible effects, become the ragemonster, and wreck the place.
That effect goes unnamed in the film so I’ll call it the bad mojo radiator. The longer people hang around it, the more discord it sows. In fact just before Loki’s thralls enact a daring rescue of him, we see all of the Avengers fighting in the lab, for no other reason than they stand in the glaive’s presence.
The infighting ends suddenly when Banner unintentionally takes the glaive in hand as he attempts to silence the group. Because the threat of Hulk + glaive is enough to make other fights seem secondary.
We never see Loki triggering this ability of the glaive. Is it just a default, going on at all times? That seems problematic if you needed allies around you to behave, or even take disguise and hide amidst people for any length of time. So maybe that’s not the most useful design.
What if this bad mojo was actually triggered, just passively? What if it starts quietly humming its Song of Discord when it is separated from its appointed wielder for some length of time? This would be an excellent anti-theft device, and even one that would make it hard to keep it hidden long.
How might we use this sort of strategy beyond the world-conquering semi-mystical, fictional sort? This strategy is one step beyond the authenticated-users-only constraints of smart weapons, adding a layer of deterrence from possession. Imagine if a gun pulled from its authorized user shocked the holder or occasionally sprayed malodor? Or a car that turned its volume increasingly louder after it was reported stolen? You can be sure the thieves wouldn’t keep it for long.