It's interesting to compare the 2017 Astros (who won the WS) and the 2017 Twins (who had a surprising winning campaign after Total System Failure in 2016). In a nutshell, the Astros bludgeoned their way to the title, and for every Astros batter who contributed hugely, the Twins had a similar candidate who came up short by comparison. All the Astros' bets seemingly came up aces; we had Buxton beset by injuries compared to Correa, and Sano beset by, well, being Sano compared to Altuve. The Astros signed a big contract with Josh Reddick, which paid off handsomely for them in their WS year and then he was below average for the remaining 3 years of his contract.
I didn't analyze any deeper, but those observations on the surface lead me to expect that the conclusion comes down to execution and luck, more so than the master plan itself.
One thing I remember, though, is that supposedly the Astros' TV ratings measured literally 0 at one point during their 3 years of 100+ losses, and ballpark attendance declined significantly during that period. It's a lesson I suppose can be taken - that Ownership has to be on board with losing money or breaking even on low revenue for a few seasons in the pursuit of potential profits down the road. The Twins seem to have a plan that involves a profit every year even if the team on the field is bad. (I also note that the Astros didn't get back above .500 before they started trading for players making significant money and signing free agents again. Chicken and egg, somewhat.)
Anyway, Terry Ryan never uttered the word "rebuild" to the best of my recollection, but it was evident when he came back as GM that that was exactly what he was doing. It just didn't work. But signing Josh Willingham and Ryan Doumit didn't impede Byron Buxton's development. Carlos Correa panned out; Buxton, at least to the same degree, simply didn't. Perhaps, with perfect hindsight, the plan should have been to take Kevin Gausman or Max Fried instead of Byron, but Correa himself was off the board on draft day.