Not at all. Lexop allows you to send files to anyone in the world without cluttering their inbox or your outbox. Documents that are sent to recipients via Lexop (with the Outlook addin or via your Dashboard) will not be attached with the email. Only links are added in the outgoing communication.
When using the Outlook addin, files are not kept. When sending a normal email, you will find copies of everything in your SENT folders, which can cause your outbox to quickly fill up. With Lexop however, only the names of the items are kept, because all the files can be found and accessed online from your Dashboard.
Therefore, no inbox or outbox clutter for anyone.