The recommendation for hodl might just be to hold on to bitcoin, but there was no specific time period slated to hold onto your bitcoin when you’re trying visualiise the term HODL into bitcoin investment. Anyone can wish to interpret it the best way possible and what they’re okay with. It could just be hodling for a four year period and sell at every bull cycle when the market is at ATH. It could be to HODL for a longer time, probably a decade plus and take profits partially at every bull cycle. It just has to be what works for you best and your own understanding of HODLing. But a four years HODLing period should be the minimum when trying to employ this popular method of HODLing.
People have different life and statuses in social and economic conditions so they have different options to do with their life including investment. A younger investor can have a longer plan while with the middle aged or the elderly, they will have kind of shorter investment plan.
The HODLing time of different investors surely is not the same and it is different by many reasons like age, social economic status, and their plans for the future from individual, family life to finance.
Basically investors must learn about Bitcoin market cycle, its history, and know of what is possible longest holding time to get profit. Base on the past data, it is about 5 years (a little bit longer than 5 years) to get profit.
https://hodl.camp/https://www.bitcoinmagazinepro.com/charts/bitcoin-profitable-days/