Some emails I receive every day to the Inbox and I send to junk
My question is, how do you "send to junk"? If you are simply dragging them, Mail won't "see" that. It might be better to use the shift-command-J ("Move to Junk" in the Message Menu,
not the "Move to >" command). Be sure you have "Enable junk mail filtering" checked in the Mail Prefs->Junk Mail.
You can also easily create/edit a Rule if you get a lot of messages with similar content/domain name/etc.
Rather than even bother with "Junque" mail at all, I use SpamSieve to just dump that stuff in my SPAM mailbox. Even then, you must 'train' SpamSieve by using its control-command-S shortcut that it adds to the Message menu. SS does learn and gets better over time. Because I use SS, I have
disabled the Junk setting in Mail Prefs.