Laravel provides the Mail facade (as of version 5.6) which acts as a wrapper around the PHP email library Swift Mailer.
Any application that sends emails needs to have logging for send events. No one wants to go wading through Linux sendmail logs or bothering sysadmins to go through Exchange logs.
Swift Mailer provides a couple of different logging plugins natively. Laravel provides decent documentation around their Mail facade but omit some details. One feature they leave out are Swift Mailer’s plugins and how to access them using the wrapper.