What does it mean if my iphone 5 charger says not supported by this accessory?

I just got a new iphone 5 charger as for some reason they stop working and I'm on my 10th, thats not including the ones I've burrowed from my sister.
So the new iphone 5 shows up on the comptuer and opens itunes but dosn't charge my phone it says "charging is not supported with this accessory?"

Http://www.gatorspit.com/tips/iphone-wont-charge.html

Hi you may have a damaged dock connector if the iphone is under a year old your warranty should cover it, you may also have a dirty dock, use a dry tooth brush an give it a little brush

As annoying as it might be, every time I get this error I unplug it (from the phone not the USB port) and quickly plug it in. Usually after about 4-5 times it works. Today I pushed it into the phone end hard and it works. Its annoying and it changes its actions every day… But it ends up working and then life goes on.