Yesterday I extended my daily ride from 15 to 20 miles. When I got back to the condo the small bag strapped to my bike was gone. It held my keys, glasses, cell phone and a few dollars. I couldn't get into my condo to get my spare set in order to take my car back along the route I had just ridden to look for the bag. So I jumped back on the bike and started to look. I did the whole 20 mile ride again to no avail. This was the first time I had done 40 miles in one day and I was spent. I'm sure losing things during a ride is not an uncommon event.
I did recover the bag when a very nice person answered the phone when called. It saved a lot of trouble although the phone was damaged. She was smart enough to take the chip out and put it in hers and was able to answer calls. I must have rolled over it when it fell. It can be replaced.
I discovered that I didn't have the bag secured to the bike properly causing it to loosen and eventually fall.
Now that I've done 40 miles in one day, my daily 20 mile ride should seem short. I will have to extend again.
Take care of your stuff.