CRM 2013 has removed the “Convert Lead” dialog box from the Lead Qualification process. Thus the product now doesn’t give the options of controlling which entity records to create upon Lead qualification.
New Lead Qualification process of CRM 2013 directly creates all the three entity records – Account, Contact and Opportunity as a part of lead qualification process, thus removing the flexibility from the user of selecting the entity records that needs be created. The product however checks for possible duplicates for Account and Contact records but the process isn’t favored by many and the risk of creating duplicate records or associating lead and opportunity to incorrect Account/Contact cannot be neglected.
I managed to find a good workaround to this problem and get the original functionality that we had in CRM 2011, though not the dialog. The approach suggested by http://leontribe.blogspot.com.au/2014/11/fixing-lead-conversion-in-crm-2013.html is to add the Status Reason field to the form and add a Status Reason of ‘Convert to Account’ (or ‘Convert to Contact’, or both). The user then simply changes the Status Reason and a workflow takes care of the rest.
Using this approach you can build in practically any qualification behavior you want. In the case of a Lead to Account conversion, you create the new Account, link it to the Lead and then change the Lead to Qualified. The workflow is relatively simple and easily adjustable down the track if the business processes change.
If you wish to hide the original Qualify button, consider a tool like the Ribbon Workbench. Also, you can combine the best of both worlds and put some code behind a cloned Qualify button which calls an Action. This combines the elegance of a button replacement with the flexibility of workflow configuration.