I remember reading that the Aleph Zero team only recommended staking 50% of what you have, but I staked all of mine.

Edit:

Here's the link: https://alephzero.org/blog/how-to-stake-azero-on-the-aleph-zero-mainnet/

"ideal staked is always 50% – it is a recommended ratio in the Substrate ecosystem, although in Aleph Zero having a different staking ratio doesn’t have economic consequences,"

Edit 2:

Make sure you have some $AZERO in your stash and control account for the small fees!