To make a deal. In common law, an agreement is viewed conceptually as an expression of an agreement between the parties. This could explain why, since a good deal is «made,» the authors are used as lead-ins. The words strongly reflect the objective character of an agreement: separated and separated from the minds of the parties. It probably also explains why an entire contractual clause has a relatively strong effect (given the legal concept of the Parol rule, whose statement does not fall within the scope of this book). I grabbed it. The first line indicates that the agreement will be concluded. If you do something like an agreement, a discussion or a relationship, you will be part of it. An agreement is a psychological rendezvous of the spirits that arises from the offer and acceptance (i.e. the spiritual consent required by all European laws to have an agreement) which is ultimately reflected (as well as possible) in the text of a treaty.
Pragmatic, simple. Whatever your preference is made and entered are largely redundant. The contract should not be started with an introductory line (which contains the title, date and names and details of the parties), but should be left open and simply use a title «THE PARTIES:».