Ronda Rousey's miraculous rookie year was both in kayfabe and reality one of the (if not the) greatest in WWE history, and with only one pinfall/submission loss, her record surpasses every other. However, she's also only worked 31 matches during this time - less than one per week and a far cry from the hundreds assembled by the full-timers making towns several nights a week.
To score highly under those circumstances reflects a huge show of confidence from the company, and it's why only wrestlers with 100 matches or more qualify for this particular ranking. Apologies are extended to the likes of Ludvig Borga, Tom Zenk and El Torito (!) who would all be present had they knocked out a few more matches during their respective WWE tenures.
Road Dogg, speaking on behalf of the organisation, once suggested that wins and losses don't really matter. He was inelegant in his assessment, but the point drilled into WWE's modern churn and just how challenging it is to book somebody persistently as a winner in the modern age. There are more Horace Hogans than Hulks in 2019 - it takes becoming an almost unassailable winner not to be a total loser.
(Gracious thanks to ProFightDB for the data used to compile this list)
Square eyes on a square head, trained almost exclusively to Pro Wrestling, Sunderland AFC & Paul Rudd films. Responsible for 'Shocking Plans You Won't Believe Actually Happened', some of the words in our amazing Wrestling bookazines (both available at shop.whatculture.com), and probably every website list you read that praised Kevin Nash.