Reverb is one of the most common and misunderstood effects in audio recording. Please do not make the same mistake of thinking that every reverb's functions to fix flaws or cover up mistakes. That would be like applying ketchup to cover up the taste of rotting hamburger. Your end result may come out worse. The only exception is when the reverb itself is the featured component. Commonly, reverb sounds its best when it provides just a slight glow or aura around the sound source and to give the sound some subtle spatial context. A little goes along way with reverb. do not over do it or your tracks and song will sound to washy and far away. But there are some times when you want that far away and washy sound. Reverb is best added on an effects send, so you can control the levels with the send volume control. Why? Because in my opinion, its best to combine the dry signal and the wet signal together through a bus.
The proportion of dry signal to reverb determines a sound's perceived distance in a mix. Inexperienced recordest-engineers often apply way too much reverb because its easy and it sound good, but there's a thin line in just enough and overdoing it. Avoid using the same reverbs and the same amount of reverb on all your tracks. Inserting the same reverb on your drums, guitars and vocals can make your song sound flat. so use different reverbs with different amounts to not make this happen. Also know that reverb buses-channels do not need to be panned at all.
Keep all these things in mind next time you grab for a reverb and remember a little goes along way. Do not drowned your mix in reverb, just like you would not drowned you're salad in salad dressing.