I've never left mine anywhere either. But there for the grace of God, go I.
Human memory is frighteningly fallible. It doesn't record events like a videotape which we can replay whenever we want. It's more accurate to say that our brains recreate our memories using clues from past and present, which includes other similar memories. It's a bit of a bodge job.
So, you might remember putting your keys in your pocket when you actually left them on a shelf in the hallway. You might start a new job, meet dozens of new colleagues and mix up two people who look nothing like each other, because they happened to be sitting at the same desk on different days. You might clearly remember Emma telling you an anecdote and be able to "hear" her voice saying the words in your mind, when you actually heard the anecdote from Becky.
And you might drive to the office with your baby son still in his car seat, because on that particular day, you had to stop off at a shop and this disrupted your routine enough to derail your memory. And later, you won't understand how this happened, because you clearly remember dropping him off at nursery. And when you thought about your son that morning, you fondly thought that as it was Friday, he would be enjoying the weekly Music Bugs session.