Watching banjo videos, there seems to be a glut of nasty, dirty banjo heads. I’ve never understood this.
Is there a reason why many players, pros included, don’t just change their heads? Do they prefer the nasty look? Or does a head wear into a better sound the older it gets?
A good sounding instrument is important to most musicians
A pretty instrument is a lower priority to many.
Time taken to replace a head and make the necessary adjustments to get the sound you already had is a waste of time to many, and could be used on something of a higher priority like…playing…
You might consider concentrating more on listening than looking 
What you are seeing may not be dirt, but simply the frosting wearing off the banjo head. It means the banjo is a work horse, not a show horse!
I haven’t replaced many heads in my time, but I do know that different heads create different tones. Heads can last a long time, so it’s even possible for the exact same model head to produce a different tone after being replaced.
Couple that with the time required to replace a head, plus the break in period, it really IS a hassle.
And this may just be my observation, but I think a lot of banjo players see a well worn head as a badge of honor. Kind of a way of saying “Look how many hours I’ve put in on this banjo!”
Doesn’t take long for a head to look dirty, most dirt can be cleaned off with a pencil lead eraser. Could work out costly to replace a head every time it accumulates dirt. Many banjo players look at a dirty head and see it as a badge off office. I have replaced my Fender head twice in 12 years
I also agree with what @Fiddle_wood & @Mark_Rocka said
I like to change them when the coating gets too worn, but the tone from an old head to a new one is not much different if tensioned properly. A Mr. Clean magic eraser will take off most of the dirt from a top frosted banjo head.
Thanks everyone! I figured it was a sound thing and less about the aesthetics. Good to get some feedback on that. I just looked at my head and it already has a grease spot where I rest my fingers. Guess I need to play more to get a real wear spot 
Hi Mike, A couple of other things I do which helps keep dirt off the banjo head. I always wash my hands before I pick up the banjo, and two I clean the strings regularly with tissues and before I put it back in it’s case. If its a hot day my hands tend to sweat and release oils on the strings.
I guess I’m in the minority view, I’d like a nice clean banjo head. @Archie’s tip about cleaning up your head with an eraser has saved me from considerable personal embarrassment, and has allowed me to continue picking uninterrupted.
Another tip I learned years ago was to put a small spot of 3-in-1 oil or gun oil on each of the tension hook thread after changing the head. Apply the oil using a small needle or nail dipped in a cap of oil allow the surplus to drip off first. That way you should avoid apply too much oil. This should keep the threads from rusting in a humid climate.
Talking about heads. We have a broom in our family it is over 50 years old. The head has been changed 3 times and the handle 4 .
Here all week!
I have only changed my banjo head three times in 43 years, or about once every 10 years. I don’t think I will do it soon, but I will probably tighten it up some once I order a banjo head device from BEN.
Mine is written on, scratched and worn but it works.
Thanks
If you’re talking about the drum dial, I can tell you from personal experience there are few things money can buy that improve the tone of your banjo like that dial. I check the heads on my 3 banjos about once a year with mine and they all sound better than they ever have before.
A banjo “settles in” over time with all of the parts put together and kept at a certain tension, etc. Changing the head moves and resets a lot of parts of the banjo aside from just the head, that can each have their own impact on the banjo tone. Sometimes, this can mean a considerable difference in tone just from changing out the head. Also, many times the wear spots are not necessarily dirt as much as they are places where frosting has worn off which can also affect the tone.
I spoke with Russ Carson at Ben’s October Cabin Camp about a prewar Gibson banjo that I had seen him play in a video. I had also heard this banjo in other recordings before. I asked if it was as good as it seemed and he said, “It was…then he changed the head.” He told me that it had been great and it was getting back to that same greatness. But, I gathered that it had lost a lot of tone temporarily, and was taking some time to settle back in.
Now, aside from all of that, I personally like the looks of a worn head. Like @Mark_Rocka said, it’s kind of like a badge of honor and gives the banjo some character.
Couldn’t agree more.
My old banjo had a head that never got dirty or worn. When I took it to a skilled luthier I learned it was a tenor banjo head, not a bluegrass head. He said the bluegrass head has the frosting on the outside. It’s on the inside with the tenor head. It’s face was smooth shiny plastic. After 25 years at sporadic picking, it always looked new.
As far as I could tell , it sounded fine. So if you like clean & shiny, you might consider a tenor head. 
Hi @BanJoe you can buy heads with the frosting inside for a Bluegrass Banjo I had one on my Fender for several years before replacing it with a Fibre Coated head. The frosted inside head produces a bright tone and the fibre head produces a much deeper mellow tone. I guess it’s all down to what your preference is.
Those bottom frosted heads are not very good for holding the bridge in place, which is why I prefer the standard top frosting.
Archie, some of us call that “concentrating” 