This is absolutely the right answer

I don't intentionally leave my trash, but sometimes I just forget. I've tucked my empty container out of the way so well that I don't even notice it, so it's not until I'm passing by the trash bins on my way out that I might recall that I had trash that got left behind.

But others who see my trash have no idea whether or not it's usual for me and don't know that I didn't leave it intentionally so to them I'll appear to be lazy or a jerk, rather than just occasionally forgetful.

How could you forget The Brattle!