Judo not a martial art? You have never been thrown I guess. Any style of combat that uses paricular skill sets, theories and applications. Most have strengths and weaknesses and are incomplete in one or more ranges.
Some depend on certain body types for best results. Weapons, no weapons, Full Contact , no Contact, belt ranking or competition results can gage progression.
Boxing, Wrestling, Shootfighting, Tae Kwon Do, Kung Fu, Brazilian Jiu Jitsu, Chess, Tai Chi, Hapkido, Sambo, Judo ............................ . I like to learn from any source and use what I find fits my mind, body and strategy. I have 73 matches between Am and Pro events in 3 and a half years of training.
If anyone is near North Jersey I run an open mat training session every Wednesday night. Details on my site.