Despite almost zero energy consumption why does my spaceship scheduled cryostasis in shifts?
In the distant future a breakthrough in cryostasis technology can put healthy people into frozen state so that all metabolism halts and cells never age a bit, the spaceship is carrying them across billions of light years hopping between star systems in search of newfound hospitable planet.
I am wondering if the journey spans several centuries what benefit would encourage people to wake from cryostasis state periodically?
The ship's AI had plotted a route in interstellar space to avoid crossing path with asteriods and high velocity giant molecular gas and clinical trials suggested that cryostasis is 99.99% safe to use.
We know that human being requires high maintenance so would it be optimal if everybody wakes at the destination instead of in batches enroute and wasting on the essential resource like oxygen and water.