When it comes to blogging (proof of brain) on the Steem blockchain I like to make the comparison with bitcoin mining.
It was fairly easy to mine Bitcoin with your own computer back in 2009 but when more people started to do the same thing it got harder and harder over time.
The same logic applies to blogging for me and I wrote about this 9 months ago.
At the beginning (a little under 2 years) some early bloggers earned well over 100.000 STEEM or more tokens with blogging in a fairly short amount of time (less than a year).
Trying to do that today is nearly impossible.
Just like Bitcoin the increase in value of the STEEM token makes up for the decrease in the amount of tokens you get for your blogging efforts.
Earning 40 STEEM token worth $0.10 a year ago, is the same as earning 1 STEEM token worth $4 today.
The difference is that if you kept the 40 STEEM you would have been even better of.
Of course holding STEEM is not 100% risk free.
If something would happen to the blockchain that would break it or something else, call it reason X than all the STEEM tokens you have are worthless.
This is the risk everyone that holds STEEM tokens (or any other crypto for that matter) takes every day.
Now I don't think this very likely to happen but I do wanted to name it.
I talk about it more in my vlog.
From one of my comments 9 months ago:
But I don't worry about these things. I'm trying to better myself as a blogger and also have invested in STEEM because I believe in it a lot. This is something I can do for myself and the Steem blockchain today and I'm putting a lot of my time into it (and loving it in the process).
If steem proves to be successful in 5 years it will have (most likely) attracted bigger names. Bigger names will scoop up more rewards because they add value to the Steem blockchain with their following (more users). In case this happens I will have a tough time competing with them with my life blogs. But I'll still be happy because I own Steem tokens.
I am a witness with our developer group 
for the Steem blockchain. If you want to support us I would appreciate your vote here.
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