I understand that Desktop Edition does not store passwords in the workbook itself due to valid security concerns.
But as a user, I connect to about a dozen different data sources, all with different credentials. Every time I open a workbook, I must look up the proper credentials and type them in at the prompt. This needlessly wastes much time.
It would make more sense if Tableau Desktop stored database credentials as a local preference, independent of the workbook itself. This is how most modern database access apps deal with authentication issues. If done properly, it strikes a good balance between ease of access and putting your credentials at risk.