ISTR someone (Elon probably, it's always Elon even when it's not, he's kind of like Mark Twain that way) from Tesla saying (tweeting, etc) quite early on in the history of Supercharging that their current model was free-for-life but that they expected to reevaluate after they had X00,000 or maybe X,000,000 cars on the road. Assuming I'm remembering accurately and that the quote was O(10^5) and not O(10^6), that's not "failure", it's "executing to [announced] plan".
Unfortunately I can't put my finger on the quote, but maybe someone else can. (The thread is snowballing fast, maybe someone already has. :-/)