Earlier quoted context omitted.
It's not impossible to estimate roughly how long something will take. If you consistently get it wrong, either: 1. You're not breaking down the work into small enough chunks to properly think about how long it will take 2. You are probably consistently under (or rarely over) estimating and should be able to fix that. For me, I have to triple my estimates, it always takes 3 times longer than I think it would To claim…
I've seen Agile™ estimation break down when the task is either 1. something nobody has done before (or has no close analog), or 2. is so interconnected that it can't be broken down. The former is just a matter of hiring more experienced engineers _or_ allocating exploratory/prototyping time. Still high uncertainty but these kinds of tasks become rarer over a time. For the latter, the common refrain is "break it down"…
Have you worked with contractors? This is so so so so not true.