Any particulates that make their way to the vapor path will also be inhaled. This can become a source of lung and throat irritation.
Grinding your flower can let tiny bits get through the screen. So, I don't grind at all and just tear a tiny bit off a flower and pop it into the herb chamber.
Some people have had success by adding a second screen to prevent plant matter from entering the vapor path
I have found that filtering the vapor can create a wonderful smooth non irritating vapor. I take a bit of degummed hemp fiber and wind it into a flat disc, then sandwich it between two CCD screens. Not only will the vapor be velvet smooth but your condenser will remain clean for a long long time and you will notice that there are no tiny bits stuck to the inside of the condenser.