I’ve been using a Fitbit since May 4, 2013. That’s right—Star Wars Day. Which seems a perfect day to have introduced a new piece of tech into my life. It’s been a great help in getting me to back away from the keyboard and move, supplementing the plans I’d already made to stay alive as long as possible.

In the 20 months since I strapped a Flex to my wrist, I’ve taken 6,909,017 steps, which works out to having walked 3,440.01 miles. And my feelings toward the product have been mostly positive. But it occurred to me today, as I wrapped a fourth Flex band around my wrist, that there’s one thing I don’t see much of online, even though my friends and I have spoken of it—that those bands wear out far more quickly than we’d expected.

Since the Flex tracks my sleep as well as my activity, I wear it 24/7, only removing it to recharge once every 5-7 days. This means that over the course of these 20 months of use, assuming I recharged at the lower end of the battery life, I would have only slipped the device from one of my wristbands approximately 120 times or so. Split that among the three dead bands, and that works out to only 40 removals and reinsertions each. (Check my math, OK?)

And yet, here’s what the stress of sliding out and then slipping back in those devices has caused those three abandoned wristbands to look like now …

Note that all the wear is in the same approximate area, and yet each is different.

So what’s up? Why are the bands giving out so quickly? Design flaw? Manufacturing issue? Planned obsolescence?

Whatever the reason, with a three-pack of bands currently costing $29.95, it’s definitely something you should factor in when predicting the total cost of the product during normal use, because based on my experience, you’ll likely need a new band before your first year is up. So while I still recommend the product as a whole, I thought it only right to at the same time pass along these few words of caveat emptor.

Now you’ll have to excuse me … I have a few more miles to go before I sleep.