Choose the shortest useful lifetime
Short expiry is a simple way to reduce exposure for offer packs, legal files, financial documents, and draft materials.
Share passphrases separately
If a link is password-protected, send the passphrase through a different channel. That keeps a forwarded email from carrying every access detail.
Use permanent links selectively
Permanent hosting is best for polished, durable assets. Temporary confidential packs should close when their job is done.