Did anyone have to get tubes for LO because of fluid, but no ear infection?

LO is 11 month, and has had 1 ear infection, but has had fluid present since his 9 month appointment without being infected. Our doctor said if the fluid is still there in 4 weeks we will be referred to ENT about getting tubes because at 3 month mark of fluid it could start causing hearing issues.

Anyone dealt with this? Any chances the fluid is going to magically be gone in the next few weeks? I guess I was kind of surprised since he hasn't had ear infections that we may be on that path.