If you are writing Omniscient Narrator, you can use any character's name up until the point 'Herbert' or 'Jeremy' starts to go 'ching!' for the reader.
But -- if you are writing in Deep Character POV, you do not want to use the name of your viewpoint character more than is absolutely necessary. In Deep POV, you use the character's name once at the beginning of the scene to identify who the POV character is. Then you don't use Marvin or Floribelle again if you can possibly avoid it.
What it is . . .
if you're doing the Deep Pov right, the reader is riding in the POV character's head, being the POV character. Nobody thinks of himself as Maurice or Floyd inside his own head. When you use a proper name, it drags the reader out of the character's head.
I don't have to tell you that nobody thinks of himself as 'the thin, dark fellow' or 'the young girl'.
When you are in Third Person, Close POV, it's 'he' or 'she' straight through. Fortunately, if you take the reader in close to experience the character's adventure rather than describing it the reader, you'll find this removes much of the need to use 'he'.
So. Not so much,
He walked down the hard, hot runway.
But
The runway was hard and hot under his thin shoes.
Not
He figured it was going to rain.
But
It was going to rain.
Not
He only one chance to kill the zombie. He had to get in close. He grabbed the knife and moved in.
But
The knife slipped in his hand, sticky with his blood. The flat, dead, cold eyes of the zombie met his. Foul breath whuffled across his face.
