How long will it take for a tortoise egg to hatch?

Like a mythical dragon, tortoises tend to hatch when they think the occasion is right, especially when the planets align, a suitable caretaker is nearby, or on a blue moon. If the tortoise is retarded (like the majority of them), then it will probably hatch whenever it feels like coming out of it's little shell. Unfortunetly, the stupid human caretakers will think that the eggs are duds and will dispose of the eggs before they want to hatch.