Had mine a few years, I was usually getting 30-40 channels. Of course some came in better than others. Since about 2 months ago, I am getting maybe 20 channels with many of them coming in really shaky. Do these things wear out? I don’t know the model info but I think it cost about $40 or so.
They can certainly get water damaged or mis-aligned.
If you are talking about a passive antenna (simply: no power applied to it in any way) then it has nothing that can wear out.* As beowulff said, though, it might be mis-aligned.
*= Technically it has parts that might corrode, or erode, but practically speaking, no.
I learned of Locast from another thread. Hopefully that will solve the issue.
You should never bend them, but as long as you apply a light coat of data lube every 7 months, they ought to last forever.
Have you re-scanned for channels? I’ve found that will usually pick up lost stations.
One possibility is that the environment has changed in a way that it causes signal interference. Perhaps trees have grown or new buildings have gone up. Something may be in the direct line between the signal and your antenna or something nearby is reflecting the signal in some odd way. And there is always the possibility of a loose connection or a cut in the wire that is causing a weaker signal. But the antenna itself shouldn’t wear out.
Stations can also be lost when antennas are adjusted(or even moved to a new location), and this happens more often than people realize. If antennas are shared you could lose a bunch of stations at the same time.
Yes, a re-scan might help. A lot of channels changed frequency or went off the air altogether a couple of years ago, due to the FCC selling off frequencies for such things as wireless 5G. All TV stations that were formerly on 36-51 had to move to a lower frequency or even share a transmitter with another station. A re-scan may help in finding those changed frequencies.
Where is the unit itself? Is it sitting on a table, attached to the wall, or in a window(preferred)?
This company’s transmitter locator should be able to determine what is available in your area. I tested it out for my location, and it was totally accurate.
Antennas Direct | TV Transmitter Locator and Mapping Tool
It picked up too much knowledge, and it plumb blowed up! 
Thanks for the suggestions, everyone. I did do a re-scan, and have moved the antenna everywhere possible. I’m going the “Locast” route.