One keeper was in initializing state

We wanted to extrapolate our keeper container from 4 GB to 10 GB, so when we upgraded the master keeper it went into initializing state and the data volume was not syncing. We observer the keeper volume was not growing and the directory was empty. After waiting for long time we stopped the whole postgres stack and started the container one by one. Started with proxy and then sentinel and then started keeper1 and keeper2 simultaneously. Surprisingly the volume started growing and finally both the keepers came up. There were no error message what so ever in the keeper logs.

Can you please share your thoughts what might be the reason why the initializing was not happening in the first place. It was just a memory upgrade. Nothing we changed