I think parent’s point still stands: expecting that X and not Y will come in 18 months might be worse than not expecting anything, if X actually comes in 36 months.
Even within the same organization, it’s such a gamble when:
- X might never come if the project takes too long or gets deprioritized. 18 months is a long time, perhaps half of an engineer’s average time in the company. X’s sponsor going away could mean the project stays in limbo for the rest of its life
- X might become Z when you realize midway that X wasn’t a good idea in the first place, or the assumptions behind X changed enough for the project to not make sense anymore. The org might not care for the cost to readjust now that X is gone, but you’re still worse off than if you weren’t waiting for X.
That's fair. This isn't a binary, and the ideal is likely somewhere in the middle.
Still, I do think there's quite a large portion of detail-planning that can be radically different dependent on the high-level expectations, even where the range of high-level outcomes is small.
i.e. (random off-the-top-of-my-head example): I'm building a piece of software offering some kind of service to end-users. We're considering staff-curated -vs- user-generated & curated content & we opt for the user-gen approach as we don't think the first option will scale. As we get into the market, we quickly realise the demand for content is high, we're in a good position to adjust our pricing upward, but engagement in content-provision & curation activities is low. So we decide to pivot to staff-curation.
The above pivot doesn't involve a radical product change (the offering remains similar overall), but does involve radical technical changes under the hood. A long-term-planning oriented company may have invested heavily in building robust (expensive & complex) community features that may be thrown out later. A short-term-planning oriented company would more likely hedge their technical decisions - leverage some 3rd-parties temporarily during user-testing, maybe test earlier, be more sensitive to priority changes.
I am pretty sure there are teams / projects for which one methodology is better than the other.
Stating that there are no situations in which it is beneficial for some team to make long term plans is simply too strong a statement.