What was Uncle Williams’ comment on the ‘tinkerers’ of the world?

The author had tried to get his watch repaired when it had run down after functioning efficiently for eighteen months. The author gave up on his watch after he took it to seven different people and spent around two or three thousand dollars on the repairs when the watch had cost him two hundred dollars only. He had understood then what his Uncle Williams had once said to him. Uncle Williams said that 'a good horse was a good horse until it had run away once'. Relating to it, the author realized that a good watch was a good watch only till it had run away once and then had fallen into the hands of numerous repairers. The unsuccessful tinkers in the world are not able to specialize in anything even if they may know something about many things. The author's Uncle Williams used to wonder about what would happen to the gunsmiths, shoe-makers, engineers and blacksmiths who became useless tinkers. Thus, Uncle Williams had implied by his comment, that the tinkers were useless as they were not able to specialize in a particular skill.