Long-term HODL must understand about the potential of Altcoin that we hold. If it's a potential Altcoin, it will benefit us later. But if Altcoin is bad, then we will lose our time and assets. Before doing HODL, we must understand very well with Altcoin that we will invest in.
Yes, before one will embark on long term investment, he must see a good case use for the product created from the project before invest. One other issue raised by the OP that's more important is that, one much have another source or sources of income before invest on a long-term HODL.