If someone is careful to use gloves correctly and disposes of them (with proper protocol) after any possible contamination and before touching their faces or their personal items such as phones, then they can protect from transmission by keeping droplets that may carry virus off of their hands and belongings. For example, wearing gloves while riding the subway and disposing of them after touching the seat would theoretically protect you from any virus that may have been on that seat. That being said, washing your hands frequently is probably just as good.
Also, apparently wearing gloves and not being careful can even increase your risk of transmission, according to one doctor in the UK.
In short, it's probably better to just wash your hands and avoid touching your face. However, if you are going somewhere public where there is a chance you'll be touching something that might have respiratory droplets on it, then you can consider wearing gloves and disposing of them promptly after you are out of that situation.