Explain to the user the difference between logging out and locking the vault

When creating an account or setting up a new app, the user should be prompted with a message explaining the difference between locking and logging out from the vault and all the consequences.
Many users don’t know the difference and there are many messages in this forum which could be avoided thanks to something like this.

It should also be described in an article in the help website.

If understand it properly the difference it quite is clear:

I think the OP meant consequences of “locking” the vault like the data remains then locally stored, e.g. encrypted by the (non-biometric) unlocking-PIN if you set one.

Here on this help site it is described (though the title is about logging in and unlocking the vault, whereas OP wrote about logging out and locking the vault, but I guess the text is about what OP meant): Understanding unlock vs. log in | Bitwarden Help Center

Addition:

That depends on what unlocking mechanism you choose:

That depends on what login mechanism you choose:

I agree, your answer is much more precise.