If a magic item casts a concentration spell does the PC have to concentrate on it?

@LexStarwalker If a magic item casts a concentration spell (e.g. bless – Necklace of Prayer Beads), does the PC have to concentrate on it?
Yes, unless the item says otherwise.

— Jeremy Crawford (@JeremyECrawford) June 3, 2015

@LexStarwalkerTotally get it from a game balance POV, but it seems odd from a conceptual POV. Any tips on how to coneptualize/explain it? The item is unlocking magical energy, but the item's user still needs to harness that energy.

— Jeremy Crawford (@JeremyECrawford) June 9, 2015