All trail cams will eventually fail from my experience. You wouldn't leave your new smartphone or tablet strapped to a tree exposed to the weather, rain, snow, ice, temp changes, bugs, raccoons, squirrels, etc and expect it to work perfectly forever. To me a big difference is in customer service and for us the best there is Covert and is why I sell way more Covert than anything.
There are cheaper "throw-away" cameras out there which may work well for a while but if you have any issues at all you will be money ahead just tossing it and buying another because the step-ladder of voice mail and the hoops they make you jump through to attempt a return is about impossible, if they will even help you at all. With Covert, I talk with a real American, explain the issue and sent it back in, within a few days they send me a brand new camera, not a refurbished unit - quick and easy