Readit NewsIKEA does? What's an example?
Adam Savage recently posted a video about his favorite IKEA cabinet:
https://www.youtube.com/watch?v=fLAAxxjM_7U
The drawers have box joints which is something I can't imagine IKEA of today doing.
It's on page 311 of their 1997 catalog FYI.
These have been quite big developer heavy companies. If companies like these don't think they can motivate the cost for Slack, I wonder if there are any than can.
Just having requirements and a specification isn't necessarily waterfall. Almost all agile processes at least have requirements, the more formal ones also do have specifications. You just do it more than once in a project, like once per sprint, story or whatever.
Now that agile practitioners have learned that requirements and upfront design actually is helpful, the only difference seems to be that the loops are tighter. That might not have been possible earlier without proper version control, without automated tests, and the software being delivered on solid media. A tight feedback loop is harder when someone has to travel to your customer and sit down at their machines to do any updates.
But almost no-one really works like that, and those three separate steps are often done ad-hoc, by the same person, right when the fingers hit the keys.
So we went full circle, again.
The more your hide something from kids, the more they crave it.
If there is no limit, they will eventually get bored of it.
Other factors are things like prevailing winds, mountain ranges, altitude and so on and on - the climate system is one of the most complex systems on the planet and even with decades of heavy study and insanely fast computers we still struggle to predict it accurately out past a week or two at most with any degree of success.