Just like working on large technical projects, there is much more to success than just technical merits. Software engineering is mostly a social endeavor, and so social factors count—I’d argue they count more than technical ones in a lot of cases. Things like:

* whether the technology fits the background of your team/org/company

* the community/official support of the technology

* the long-term trajectory of the technology

* how the technology fares when used with groups of engineers, instead of individually

* social proof

* how easy it is for the existing job pool to learn the new technology

* if the technology has strong documentation

And there are more. These are more critical to me than eg goroutines. (And Go is my go-to language these days.)