Can't I just use an indoor LED light outside?
You could, but the consequences won't be pretty. Indoor bulbs are meant to be used indoors. Inside our homes and offices, we rarely have sudden changes in temperature, storms, swarms of insects, extreme cold, or extreme heat. But all those things can, and usually do, become a factor outside.
Outdoor lighting is made of materials and bulbs that are meant to stand up to these kinds of issues coming up day after day. Indoor bulbs are not. Being the more resilient of the two types, you might have better luck using an outdoor bulb inside, instead. Be sure to check the manufacturer information on your bulb or fixture's packaging regarding where it is suitable to use.
