[gnuvince]

I think the author address that point in the introduction:

> Experts, who are deeply familiar with the product, have learned its many intricacies, developed complex, customized workflows, and regularly exploit its most elaborate features, are often defensive and resistant to the suggestion that the design has flaws.

Having spent dozens, even hundreds, of hours learning the intricacies of the Git command-line, it must be extremely shocking and insulting when you are told that those efforts were in vain, because the original UI was not very good and an alternative can be grokked by people of varying levels of technical competence with only a fraction of the effort you put into the original thing. I think this is what we're seeing here: people will try and defend their time investment by arguing that a professional would learn the hard thing and not lower himself to easy-to-use tools, that the new UI hides some powerful features that are rarely used, etc.

[austinjp]

Indeed. Also known as "sunk cost fallacy".

[IshKebab]

I think it's a little different from that actually. That's normally about the merits of ongoing financial investment, but I get your analogy and there should be a name for it because you see it all the time from compsci types.

How about "sunk knowledge fallacy" or something like that?

[cies]

> "sunk cost fallacy"

I like to spot those, did not see this one though, but indeed, sunk cost fallacy it is. Well spotted :)