I used to use reversals. I don't any more because I don't like to see the cards reversed, especially when the cards aren't the standard Rider Waite cards. It annoys me to see beautiful, meaningful pictures upside down. I found once I started to become more intuitive with the cards, that the upside down pictures somehow interfered with the process and I found it more difficult to read intuitively by looking at the pictures.
I now don't find it necessary to read reversals though I do sometimes use them just to keep in practice and to make sure I'm still happy not using reversals. I find the surrounding cards and the question help to determine the meaning of the cards. I see the cards as having a "scale" of meaning. Each card has positive and negative meanings and it's not necessary for them to appear reversed for those positive or more negative meanings to be present.
When I did use them, I used them to indicate a number of situations. Just about every author has a different take on the meanings for reversals. If you want to start to learn to use them, I suggest you just pick a couple of meanings for reversed cards, so you don't get overwhelmed. Generally, reversed cards indicate that you need to be more attentive, that the energy of the card isn't quite right. For example, the energy may be blocked in some way (which doesn't necessarily mean the energy isn't going to be present in the future), or it could mean the querent is resisting the energy of the card.
The Ace of Wands reversed for example, could indicate that a project that the querent is trying to start is stalled due to someone else's input. The 8 of Cups reversed could indicate the querent is resisting leaving something that is no longer useful to them.
So the energy that is blocked or resisted could be to do with the actual situation (external influences) or the querent.