18650 batteries are designed and manufactured primarily for the auto industry and OEM power tool industry. They are meant to be used only in battery packs which have their own protection circuitry and battery management system. They were never meant to be used solo like we use them in vaping. The fact that they are available to us vapers is often there is a surplus supply available for independent battery suppliers to buy and sell.
18490/18500 batteries are not used by the auto industry or power tool industry, so the big four (LG, Samsung, Sony, and Panasonic/Sanyo) do not manufacture them. To my knowledge, only a few China battery "manufacturers" make them for the flashlight industry: AW, Efest, MXJO, and maybe the Trustfire/Surefire companies.
No question that AW makes the best 18490 battery: 18 amp continuous discharge rate and 1200 mah (specs you can trust). Compare those spec with the two varieties of purple Efest 18500 10/15 amp cdr 1000 mah battery and MXJO; and we all know how Efest and MXJO exaggerates their specs.