Reversals are optional. Plenty of professional readers work upright-only and lose nothing, because a difficult message will find another way through. If you do use them, pick one interpretation model and stay consistent — mixing models mid-reading is where confusion comes from.
The four workable models: blocked (the energy is present but not moving), internalised (it is happening privately rather than publicly), excessive or deficient (too much or too little of the card's quality), and delayed (the right thing at the wrong time). Internalised is the most forgiving and the most often accurate.
What reversals are not: opposites. The Sun reversed is not darkness. It is glare, or joy that cannot be shown, or warmth arriving late. Reading them as negations flattens the deck into good and bad cards, which is the one habit that keeps a reader shallow.