I have so many colleagues with that sentiment who give terrible plans because ¯\_(ツ)_/¯ it’s research. They mostly talk about timelines for the big end goal pie in the sky, and they’re generally wrong. That was me when I was more junior.

I also have colleagues who promise small concrete incremental deliverables in predictable timelines. They rarely talk concretely about the big end goal pie in the sky’s timeline, but generally deliver the big thing sooner anyways.

The answer isn’t making reasonable estimates of an inestimable thing, it’s providing reasonable estimates for the reasonably estimable pieces. Instead of “we’ll have ultra mega science in three to five years!” it’s, “we’ll have this specific piece of the stack built by 2022 and we hope it’ll enable these other slightly less concrete things towards ultra mega science.”