The wizard aborts at about 10% in step 9. Everything I could find in the logs was this here:

Unknown SQL Exception 1468 occurred. Additional error information from SQL Server is included below.

The operation cannot be performed on database “Sharepoint2010_UsageDB” because it is involved in a database mirroring session or an availability group. Some operations are not allowed on a database that is participating in a database mirroring session or in an availability group.
ALTER DATABASE statement failed.

Seems legit to me, since I moved all databases to a SQL Server 2012 Always On environment…

Technet says:

We do not recommend that you mirror the Usage and Health Data Collection Logging database. A SharePoint environment can continue to run if this database fails, and this data can be quickly regenerated.

So I removed the Usage DB from the Always On Availability Group, ran the wizard again and it worked.