You haven't been into trailcams much if you haven't done this at LEAST once. My best set up went four weeks in "view" mode because I forgot to switch the camera back to "photo" mode. I have homebrew cams so it got in a hurry and forget switch it back.
Then there's the time I left the dead batteries in my camera for a couple weeks on some hot rubs. Swapped out the Memorystick but forgot to replace the batteries. Nicely done, dumb ass.

And the time I hiked into a nasty hole without my keys. Couldn't check it. Stood there cussing at a box on a tree. Good times!
Or the time I forgot to pack new batteries in and was forced to just pull the camera. Now I have my "trailcam" pack with all the stuff I need already loaded up and ready to go. Keys for the locks, batteries, memory...everything.
Learn from my mistakes.