What is the the most important in B2B sales presentation?

In my opinion, in B2B it's the relationships and your reputation that count. It is necessary to build trust and a sense of understanding. If this is lacking on either side you should let go. If I didn't know the client before, good listening, a sense of uniqueness and lack of pressure to sign a contact also works well in my B2B contracts. This allows you to get the Client's attention and curiosity, and continue as above. ;) Good luck!

A good sales deck, and salespeople that understand they are present to listen to problems, and offer solutions.