User blog comment:CaptainMacMillan/Ok Battlefield Wiki, BC2 OR BF3?/@comment-202.89.176.216-20120119023616/@comment-28584497-20120122230553

Motion mines have a very limited life, regardless of whether they're destructible or not; the MAV has a million countermeasures and is a bitch to hit with small-arms, which are just about the only thing it can't evade. Everything else all the dude controlling it has to do is leave the controls for a half-sec, and the lock is broken.

And if you can't use it "on the fly" you're doing something wrong.