The pressure is off, and a couple can simply savour the truth of their loving feelings, as easily expressed through a kiss or caress as through genital sexual intercourse. Sex becomes more of an adventure, a chance to discover that there are many ways to touch, many parts of the body that are highly sensitive. That orgasm can take new forms. In fact, disabled sex can be even better. Sensuality is, by its nature, driven by deep emotions.
Stronger feelings make for better sex.
For a disabled person, sex can become much more precious exactly because of the existence of limitations. The principle holds that once you have lost certain options the others become more precious. It makes for a heightened sense of the miracle of human sexuality.