Well most in the community are doing the same, They would sure buy on an All time low and sell on the All time high, Rinse and repeat, Very simple strategy for a hodler, But there are some who surely risk they even sell on an ATL because they only believe that the price will surely drop, Well I really think there are no other system on how you can properly Buy and sell on the market of Cryptocurrency.
That is why I use an ATH as price point that signifies selling. But trust me a lot of people when in an ATH dont do this, instead they think the price will keep going up. And sometimes it will but rest assured it must drop before going up again to surpass the ATH and go to a new ATH. I just feel buy simply selling at an ATH, it takes away all the guessing and whatnot