Firstly, there are 2 main types of pool coatings: Chlorinated Rubber (pool paint, rubber paint) and Epoxy. Chlorinated Rubber is a cheaper maintenance type paint which lasts 1-2 years before needing to be recoated. Often used in council pools which are recoated each winter. It requires an absolutely dry surface of 7-14 days drying, is very smelly, and is not easy to use. Not recommended, if seeking a long-lasting finish.
EPOTEC is called a high build epoxy coating, meaning it goes on thick to give you maximum thickness and thus durability in only 2 coats. All others spread out too thin and therefore you need 3 coats to get the same thickness and equal service life.

This is what paint that's too thin will look like after a few years. You can see the roller marks on the bottom. EPOTEC goes on thick, so this does not happen.
Also, EPOTEC has no thinners, but is specially designed to flow out easily by brush, roller, or spray, to get the thick coating your pool needs to resist wear and tear over the years. Other epoxies have thinners (up to 50%), meaning they look good when applied but spread out too far, and are not thick enough to last. If you want them to last, then you need 1 or 2 extra coats. More work for you, at the beginning and often after a few years, when you see it wearing through.
EPOTEC being 98% volume solids*, when applied at our specified coverage rates will provide a nominal dry film thickness of 320 microns (about 5 times thicker than house paint). For other leading brands, the thickness is around 200-250 microns (only 60-70% as thick) - not thick enough to last. You will need to apply 3 coats or come back after a few years and apply more.

Paint worn off on steps, leaving bare concrete showing. A high wear area that requires a thick coating if it's to last.
So if you are comparing epoxy coatings before deciding, make sure you are comparing the thickness of the final finish, and not just the price of a can of epoxy with 50% thinners that spreads out well; so well in fact, you do not have enough paint thickness to stand the test of time.
See our website for helpful information and more images of EPOTEC in action at www.poolpaint.com.au.
*Volume solids is the amount of paint left after its dried, the higher it is the better. 100% solids will deliver 100% dried material, and 50% volume solids will yield only 50% of the original thickness after its dried.