Fortunately, it was a query that I was recently able to pose to both star Dan Stevens and director Bill Condon.
As great as Walt Disney Animation’s Beauty and the Beast is, there is one significant flaw in its storytelling.
This is an issue that the new live-action adaptation avoids by both removing both the 21st birthday plot point and the “10 years we’ve been rusting” lyric… but this still leaves the question of how long the curse has lasted in the new film.
Lumiere establishes in “Be Our Guest” that the curse has lasted for 10 years — but since the curse is meant to end on the Prince’s 21st birthday, that means that he was only 11 when the spell was initially cast (and that he was totally justified in not letting a stranger into his house while alone during a storm).