I was flying yesterday and I changed my pre-flight procedures regarding battery placement for the first time.
Until yesterday I inserted the battery with the rear flap up and pushing it down once I was satisfied the battery was properly seated. But doing this doesn't always produce the reassuring 'click'. I know the battery was always seated properly. Indeed, I'm anal about it, but the click was not always evident.
So, with threads like this in mind, I changed my procedure so that now I slide the battery in with the flap down. Now I can hear the click.
I recon it just goes to show that no matter how experienced you think you are, there is always scope for improvement and a willingness to refine your techniques.