The delete button seems to be available on some records but not on others. Why is this?
Your ability to see the Delete button is dependent upon various things.
For many records (People, Organisations, Opportunities, Leads, for example) you need to have the Delete permission, in order to delete the record. By default, most records on Workbooks are set up to allow the Owner (ie, the User to whom the record is assigned) and anyone in the System Administrator group to delete a record. It's possible however that your System Administrator has amended these settings. You can check the Sharing Permissions for a record by clicking the Sharing Permissions padlock icon on a record. Here you'll see which Users or User Groups have which Permissions, including Delete.
However, there are some records that cannot be deleted, such as Posted Transaction Documents. You can delete them whilst they are still in Draft but once Save & Complete is clicked, the status changes to Posted and no Users (including System Administrators) can delete them. This is to retain the audit trail for your transactions.
For a similar reason, once saved, a Case record cannot be deleted by any User.
In addition, some records cannot be deleted if they've already been used within your Database. For example, if you've added a Product to your Product Book, it can be deleted until such a time as the Product has been used within the Line Item of a Transaction Document.
Finally, you cannot delete an Organisation or Person record that is referenced within a Transaction Document unless you delete the Transaction Document first. (Remember, you cannot delete a Transaction Document that has a Status of Posted.)
You might like to know that our Summer 2012 release, which we hope to release shortly, will include the ability to delete Cases. The release will also include the ability to delete records in bulk.
A Bulletin will be sent to all System Administrators to advise when the new release is going to be available.