I presume you mean his protagonists Oh, yes. Self-effacing and diffident yet tough as nails; tougher, in some cases. But more, they recognized that they dare not count on the world being fair to them, and that while there are good people there are also always going to be ones who use and abuse other people.
I always felt that a great deal of incidents he saw or was part of in real life; for ex. that some trainers will always blame the jockey if the horse loses--never mind that the trainer may have sent it unready.