Steve O’Neill was over .500 every year as a manager, four different teams; though he only won a single pennant. What’s the record? Joe McCarthy managed in 24 seasons, all winning records. That has to be the record, right? O’Neill must be fairly high on that particular list, with 14 years.
Alphabetically, managers who had 14 consecutive winning seasons:
17 Sparky Anderson
14 Cap Anson
14 Fred Clarke
15 Bobby Cox
16 Al Lopez (if you count going 6-5 as a season)
24 Joe McCarthy
14 Steve O’Neill
14 Joe Torre
16 Earl Weaver
I might add that John McGraw had 27 winning seasons out of 29, and that Stengel was 12 for 12 as a Yankee, but 1 for 13 otherwise.
So, yes, O’Neill is in second place behind McCarthy with 14 years of never having a losing record; altho both Lopez and Weaver had their streaks start at the beginning of their careers. If only they hadn’t un-retired.