Waite was the most cautious and the most learned of the Golden Dawn generation, and he disliked practical magic. His instinct was mystical and Christian; he wrote long, careful, exasperatingly circumlocutory books on the Grail, Rosicrucianism, Freemasonry and Kabbalah, and he was scathing about occultists who claimed pedigrees they could not document, a discrimination that reads well in retrospect, given the company he kept.
He is nonetheless remembered almost entirely for the tarot deck published by Rider in 1909, which he designed and Pamela Colman Smith drew. The single innovation that made it dominant was hers as much as his: fully illustrated scenes on the thirty-six numbered minor cards, where earlier decks had shown only arrangements of suit signs. That decision is why the deck can be read pictorially by a beginner, and it is the reason it displaced everything else.
Smith was paid a flat fee, given no royalty, and for most of a century was credited as an illustrator or not at all. The deck is still widely called the Rider-Waite. The scholarship correcting this, the Kaplan, Greer, O'Connor and Parsons volume of 2018 is the substantial one, has established her as a designing collaborator rather than a hired hand, and the name Waite-Smith is now standard in careful writing. Waite himself, to be fair to him, described the work as done to his designs but under her hand, and did not conceal her.