Why Is The Year Of The Coin Missing?

Thank you Coop...

I'm going to try again tomorrow with getting
better pictures in hopes of reposting a couple
that were blurry, but are these missing numbers
considered an error coin do you know?

There could be a small premium but the condition is a little low and the weak spot is kinda small. There are collectors for these but the more that's missing the better.It is a keeper though.
John1

What CoinHuntingDrew is telling you, is that they use grease on the dies as part of their maintenance. Sometimes they don't get it all off before they strike coins and it blocks certain parts of the design/devices. The devices can be partially visible or not apparent at all. These coins are struck from a " Grease Filled Die". The coins that have completely missing devices are more collectable than those with partial missing devices.
It is nice to have a full date so one knows what year it was minted. Interesting locations of missing design adds collector interest, as does a coin with little wear. Eye appeal is important. Coins struck from a Grease Filled Die are towards the lower end of the monetary spectrum in Variety and Error coin collecting.
I will show you an example of one with completely missing devices.

Thank you CoinMasters and Coop. That's so interesting to know why it comes
Out like that :)

@ CoinMasters
I saw this the other night before I got called out of town and
I was looking at your nickel you posted above. You got my
curiosity going and I could of sworn I had an old nickel with
missing letters on the back. I could not find it, but Ihave a 1939, a couple
1940's, a few 41's and 46 nickels along with a couple others.
Almost all of them the back is pretty worn but all lettering
Is there. So it's just the missing lettering correct? I know
on the 1939 the is a little bubble on the tip of his nose that
Kind of makes it look like he has a mole or something. And
on one of the 1940's there is this weird circle on the back right
in the middle of the building, but is it just the missing letters and
numbers? I've only kept them because I love all the older coins
but is there anything to watch for with the older nickels?

Thank you CoinMasters. I had wondered about the nickels cause I was coming across so many older ones I had
wondered if maybe no one really held onto them compared to the wheat pennies. I held onto them anyway because I love
the older coins and coins from other countries. Later when I get on my other lap top I will post two of them that I found
interesting. But the one that kind of looks like he has a mole on his nose makes me giggle everytime I see it. It's tiny
but it's eye catching.