[smcl]

Correct, he didn't need to do them at all. He went off and did them anyway. This is what Yak Shaving is - optional, nested distractions that you engage in and which take you away from a task that you intended to perform. I don't understand what you mean about prerequisites.

[PeterisP]

In the original yak shaving story, every next step was not an optional distraction but was a prerequisite to doing the previous thing; often caused by 'tech debt' (e.g. the protagonist couldn't borrow the tool you needed from your neighbor because he hadn't fulfilled an earlier obligation, and needed the yak hair to do that)

[shagie]

Don’t Shave That Yak! - https://seths.blog/2005/03/dont_shave_that/ (this is the original with the borrowed EZPass)

2020 https://news.ycombinator.com/item?id=21930441 (81 comments)

Don’t shave that yak – God loves lazy programmers https://petewarden.com/2010/06/26/dont-shave-that-yak-god-lo...

2012 https://news.ycombinator.com/item?id=4034034 (3 comments)

[Izkata]

The third link has a link to http://www.catb.org/%7Eesr/jargon/html/Y/yak-shaving.html

> [MIT AI Lab, after 2000: orig. probably from a Ren & Stimpy episode.] Any seemingly pointless activity which is actually necessary to solve a problem which solves a problem which, several levels of recursion later, solves the real problem you're working on.

So yeah, both in your first link (mostly) and here: prerequisite - something you have to do, not a side thing like the clip of Hal. That GIF has apparently been misused this whole time, muddying the issue.

(The first link ends with the equivalent of "you can avoid yak shaving by introducing technical debt")