There are a lot of consumers out there that are purchasing rewrapped batteries, such as Vamped, Imren, AWT, Efest, and the like...many of which have grossly inflated ratings on the battery wrap.
There is an excellent article written by "Mooch", one of the vaping industry's most important people when it comes to battery safety. The article can be found at the link below.
http://vaping360.com/there-are-no-18650-batteries-rated-over-30a-yet/
Vaping 360 is chock full of excellent articles like the one above.
Below is a link to an image showing the true ratings based on testing from Mr. Mooch himself. Keep this link as a reference when looking to purchase new batteries and/or throwing a new build in your RDA if you happen to own some of the batteries listed. The batteries found in the image are the most common cells found and used in the vaping industry.
https://www.e-cigarette-forum.com/forum/attachments/image-jpeg.530587/
I can't stress battery safety enough. Know your mod, know your batteries, know your build...and vape safe!