Then the days turn into weeks turn into months and maybe you forget about it yourself, it's not top of your list of things to do, you haven't really missed it anyway. It flitted into your mind for a moment when you were having a sort through some old bits and pieces: oh I wonder if they've forgotten... but then.... nah, how could they?
And then maybe the months turn into, well, more months, perhaps even years... and it's just too embarrassing to bring up something you really should have mentioned long ago. Too embarrassing. For whom? For you? Or for the friend to whom you lent that... whatever it was you lent them. In my case, various friends, whose lives have taken them on journeys far more shambolic than my own, so much so that I really would feel like an insensitive idiot now asking if they could return that tatty old paperback I lent them five years ago. So I let it go. Think of it as a gift, maybe; it's only 'stuff'.
Some of the stuff I (and in some cases, we) have let go of include two little shaped wooden badges depicting Yellow Submarine style images of Paul McCartney and George Harrison (bought during a hilarious 'Beatles' weekend in Liverpool), a 1980s drum machine (hours of fun!), a packet of gig photos from a night at The Pink Toothbrush, a bootleg video of 'A Clockwork Orange' from the days when it was still banned, and a Be Good Tanyas CD. But then, does the fact that I even remember them mean I haven't really let go after all?!