How do you tell when a wine is ready to drink?

When asked at a tutored tasting when his Grand Cru Chablis would be ready to drink, the maverick Burgundy and Luberon producer Jean-Marie Guffens replied in his usual opaque way “It’s not a question of when the wine is ready, it’s a question of when you are ready”. Guffens was, I think, attempting to get away from what he saw as the tyranny of ‘the perfect moment’, the year, the month, the day even, when a wine is ‘at its best’.