I have an even harder time now since one of my cars automatically locks when I walk away while the other doesn't. I've been so spoiled by that functionality.

Luckily the other car will at least notify me if I leave it unlocked and can lock it through my phone. Would be nice if it just also auto-locked.

My not-even-all-that-new car just locks automatically shortly after you close the door, so there's nothing to "forget".