It is the luck of the draw. If you are lucky, you end up with cameras that are consistent workhorse, but if you are unlucky, you end up with duds that may not be worth its weight as a paper-weight.
Over the years, I have had numerous cameras that failed on me. My cameras are on 24/7 so the use is almost continuous. Here are some of the cameras that have failed on me:
1) I have a Trendnet model that does not work wirelessly on Day 1. I ended up using it as a wired camera (set it just next to my router).
2) My first IP cameras were bought about 8 years ago (when my eldest was born). In fact, I had two Linksys WVC-200. One has died, but the other is still working.
3) Both my Dlink DCS-6660G and my LevelOne (same OEM model) have died. The heat generated from both cameras were quite intense, and their plastic antennae literally crumbled due to the heat over time.
4) I bought three Dlink DCS-5635 cameras. These listed as over S$1K during launch (it has 10 times optical zoom). Two of them have issues with the sound (crackling sound could be heard when viewing/listening to the camera). Only 1 is being deployed. Great feature set, but not much firmware update.
5) I have two Edimax, but one has failed after over 2 years. The other is in storage as a back-up/spare.
6) I have 3 China-made no-name brands that I bought from Mediapro (F series, H series and another that I cannot remember). One of them has its power adaptor failed on me. Replacing it with a multi-volt adaptor solved the problem. Guess what? All 3 are still in use in my home.
7) I have at 4 Aztech, one of which is a PowerLine camera. Couldn't get the Powerline one to work with my network (even though I was using Aztech Homeplugs at that time). Now sitting in the storage box. Two are deployed at home, and one is sitting as a spare.
8) I have three VStarCam, two with external housing. One of them is deployed, as is the 3rd. Both requires reboot occasionally.
9) I have one Samsung HD Pro. One of the newest camera for me. Requires the occasional reboot too. However, there are times when it just stopped working, but began working the next day with no rebooting.
10) I have one Foscam. Kept as spare and not deployed.
11) I have one Panasonic VT something that is being deployed. No infra-red, but doesn't require reboot as frequently as the others.
12) I have one TPLink. Deployed at home. Sometimes, cannot see anything, but then, it comes back up after a while.
I have two broadband connection, and set up two RT-AC87U routers (actually 3, but the 3rd was set up as a wireless bridge). All cameras are connected to only one (2.4 GHz bandwidth). Some like the WVC200 is still on Wireless G, while most are on Wireless N. No Wireless AC cameras yet, and no 5 GHz cameras yet. Thinking of switching to an AC3200 for better bandwidth control, but then if there are no AC cameras, not sure what value the AC3200 router would serve.