The fallacy would be giving the first option some sort of financial value because you spend time and money on it in the past.

But when we have sunk costs, we really have a past investment that we have an unknown return upon-- and we're deciding whether to abandon that investment.

If we've made a substantial investment, it can make sense to have a bias towards avoiding actions that definitely invalidate that investment-- a bias towards inaction.

It's rare that a position presents itself where it is completely clear what the future value of different tracks is worth so clearly.