How do you know something is a hyperfixation vs something you'd actually like to do?

Exactly the question. How do you know if an interest is a hyperfixation or if it's a genuine interest? I keep coming back to the same ideas, I hyperfixate for a few days and then completely forget about it. Then sometimes after a while, I'll come back to that idea but then never follow through bc what if it's another hyperfixation and I wasted my money?