Start and End date fields not available on the Lead form even though I have added them to the preferred form

Question/Problem:
 
The preferred lead/prospect/customer form includes the Start and End date fields but these do not appear on the form.

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Answer/Solution:
 
The Start Date field only shows up in the form if the entity is already a prospect or a customer. The End Date field on the other hand, only appears if the entity is a customer. The Start and End Date fields do not appear at all on the form when the entity is still a lead. Remember that leads do not have any transactions associated with them while prospects have either an estimate or opportunity record. The Start Date of a prospect is auto-filled with the date of the estimate or opportunity attached to it. The End Date of a customer is user-defined.