A standard men's suit is designed to look best while standing. It gets a bit baggy while seated. That's a problem for people who are usually seated, specifically, in a wheelchair.
In 2004, a journalist who uses a wheelchair approached fashion designer Izzy Camilleri and asked her to produce fashionable clothing that fit a wearer well while using a wheelchair. Camilleri went on to found IZ Adaptive, a company that produces just that. It has a wide range of fashionable clothes for men and women.
For example, this suit jacket comes in two pieces. The user puts it on one at a time, then zips up the back. The arch cut in the back prevents bunching-up while in a chair.
-via Marginal Revolution