When transactions arrive from your Online Banking account, MoneyWiz will try to automatically categorize them for you, possibly creating new categories (if it thinks that none of the existing ones are suitable). This guide provides instructions on how to disable or change this process. If you like what MoneyWiz is doing but are not happy with the results, please see this guide instead.
In order to control whether MoneyWiz will automatically categorize your transactions or not and whether it should create new categories for you, please edit the account in question, switch to Extended tab and find two settings near the bottom:
Automatically categorize transactions -- disabling this will prevent MoneyWiz from attempting to categorize new transactions.
Automatically create categories -- disabling this will prevent MoneyWiz from creating new categories. It will try to fit one of the existing ones and if it fails, it'll just leave the transaction uncategorized.
The “Update balance on each refresh” setting is explained separately here.