At what point does a side project stop being “just a side project”?

Many products start as experiments built at night or on weekends.

At first, there’s no pressure just curiosity and momentum.

But at some point, expectations creep in: users, revenue goals, support, roadmap decisions.

That’s usually when it starts to feel more like a responsibility than a hobby.

How do you personally decide when a side project deserves serious commitment or when it’s better to keep it lightweight and experimental?