Which one is more natural: "the light isn't turning on" or "the light won't turn on"?

Question

Can you please tell me which one is more natural: the light isn't turning on or the light won't turn on? For example:

The light in the bathroom isn't turning on, so I guess I need to go out to buy a new light bulb.

The light in the bathroom won't turn on, so I guess I need to go out to buy a new light bulb.

If both are perfectly natural, I'd like to know if there is a nuance of difference between the two? I've refered to my grammar books for an answer, one of them was Practical English Usage 4th edition by Micheal Swan, but unfortunately they don't provide an aswer for such a specific context.

Answer 1

They're both natural to use in that context, though they have slightly different meanings, which might influence which one you choose to use.

"The light in the bathroom isn't turning on" is an observation of a current situation.

"The light in the bathroom won't turn on" is also an observation of the situation, and it carries the nuance that some effort has been made to get the light to turn on, and you have concluded that it cannot work.

So, if you flipped the switch a few times, took off the light fixture cover, fiddled with the bulb, and checked the electrical connections to the fixture, then you could say, "it won't turn on".

But if you just flip the switch a few times and give up, you might want to stick with "it isn't turning on.

Answer 2

Either is natural and would be understood. The difference is a question of time.

The "isn't turning on" form refers to the present. "Isn't" is short for "is not." The condition applies right now.

The "won't turn on" form refers to now and the future. "Won't" is short for "will not." So this form implies that the light is not lighting right now and "will not" do so in the future.