When to stop NMT?

I'm curious to know, in the realm of cryptocurrency and finance, when exactly should one consider stopping a non-marketable token (NMT) investment or venture? Are there specific indicators or milestones that should be met before making such a decision? Understanding the volatility and ever-changing nature of this space, what factors should investors weigh when evaluating the continued viability of an NMT project? Furthermore, how does one differentiate between a temporary setback and a more permanent decline in an NMT's potential?