Tired vs Weary

There's a difference between being tired and being weary.
Being tired is usually a sign that you need more rest. And it can be a good thing. A good productive day will make you tired.

Being weary could be a sign of a vision problem. You may have lost sight of the vision or maybe you've forgot it entirely. You can be doing good things and get weary. A fresh vision will usually address the weariness.