How much minimum time one should stay in a company so that it will not impact resume as a software developer

One of my previous directors had a thumb rule, any tenure with less than 3 is straight reject unless other tenures are very long like 5+

2 yrs. But even 1 yr is fine if you are having at least one long tenure. It depends on the overall pattern. Once I saw a resume where a guy having 6 yrs experience had worked in 5 companies, all his experience was of below 2 yrs duration, some even less than a year. Surly that gives a very very bad impression. I mean in any big company, you can’t learn much in 1 year, so jumping that soon means you have zero learning and only interview cracking skill, makes a very bad impression