Here is the TL;DR bullet list:

1. To help others (and possibly gain IRL Karma points).
2. To train/gain/increase/improve my experience, knowledge, patience and user support skills, in a way that no PhD or academic course could ever do.
3. To feel accomplished, in a way similar to playing video games:
   • If I can do this task, I can do other tasks as well. If not at the moment, I'll try and try again until I can overcome this (semi-artificial) hurdle.

And if you can find the time and are willing to do so, please do your best to also help others as well!


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Longer explanation:

I've been meaning to write this blog post for years and for this past week or so I've been getting back to try and help more people here at the OpenFOAM forum (and sub-forums), writing at openfoamwiki.net, as well as tackling OpenFOAM various bugs reported by the community here on the forum, at the OpenFOAM Foundation bug tracker and one or two at ESI-OpenCFD's bug tracker.

So... Why do I contribute so much to the public OpenFOAM community so much?

1. To help others
I've been taught since young that helping others is pretty much a must when living in a family, community and society, specially since not doing so usually results in the demise of said group. Which has many times left me wondering: "Why isn't common sense? Why can some people be so selfish and egocentric and not see the benefits of helping others?"

It feels that in my lifetime I've seen more people acting selfishly, rather than cooperatively. It's part of the human nature, survival of the fittest, but it can also result in the termination of whole groups of people, simply because they didn't choose to cooperate. Several religions and cults have appeared due to this very reason, to combat the selfish behavior of humans... but that is a topic for a whole other blog post...

Back on topic, helping publicly people the forums, wikis and so on, is a way to productively assist many with one effort at a time. Furthermore, eventually the residual cost per person converges to zero, with the increase of the number of people helped by each post; let me explain this with my favorite example:

1. Look for a thread or post that describes a problem and assess if I can help.
2. Once found:
   1. Either take the time necessary to solve the problem and write the solution, along with auxiliary material if necessary;
   2. Or write what I know at the moment, preferably pointing the person in the right direction with one or more links as well.
3. It may cost me 10-20 minutes to answer each post (yes, that's roughly my average), and sometimes take 2, 4, or even 8 hours to solve an issue.
4. Multiply the time spent on that written post by a cost factor, e.g. if the cost on my part was 20 Euros per hour, this means that spending 8h during a weekend would have cost me 160 Euros in money not earned.
5. However:
   • If 160 Euros are divided by 100 people that I helped, that means that it cost around 1.6 Euros per individual.
   • If 160 Euros are divided by 10000 people that I helped, that means that it cost around 0.016 Euros... 1.6 cents/person.
   • If 160 Euros are divided by 100000 people that I helped, that means that it cost around 0.0016 Euros... which rounds out to 0.00 Euros/person.
6. So from a pure discretization perspective (and ironically associated cumulative errors), it will eventually have cost me 0.00 Euros to help others during those 8h.

As a counter example: If I help only a single person on a private message, I lost X.Y Euros/hour it took me to answer that single person... which from my perspective, is rather selfish of that person


As for In Real Life Karma points: Quoting from https://en.wikipedia.org/wiki/Karma
Referring to it as points is just a nice discrete way of thinking about it


Which leads me to my next reason(s):


2. To train/gain/increase/improve

Knowledge and experience must always be earned. A person may be born with a gift, but honing that gift is always a must, in order to properly make it use. Countless books, video games, TV series, cartoons/anime, movies, and so on, teach us that knowledge and experience must be earned. Simply take a look at how successful people achieved what they have... always through earning knowledge and experience and putting it to good/profitable use... never taking things for granted.

So to train/gain/increase/improve my own experience, knowledge, patience and user support skills, I've taken the liking to do it here on the forums, wikis, issues trackers and so on. From my own past experience, this is something that no PhD or academic course could ever do, if I didn't go and explore on my own, beyond what I was taught.

And there have been countless times where by helping someone during a weekend, it gave me the answers I needed the very next work week at the office: bug X, Y or Z was what blocked us from solving a problem that had seemed to appear from nowhere... but I had already tripped over the solution during the weekend, so I had my cost recovered in little to no time to solve the problem at that moment.

BUT, keep in mind that the answers do not come easily for me either. I have to solve the problem posted in front of me, which means that I will have to grind the problem on my own, dividing the issue in as many smaller parts as necessary and solving one issue at a time. The difference is that I already have the experience needed to tackle many of those smaller problems.
And then I have to do what many engineers/scientists never do: to write down the solution, step by step, and not simply just the end results and subsequent conclusions. That takes time as well! It's not just a matter of prescribing some pills to make a headache go away... as some forum members think this is all about

That said, even after over 10000 posts here at CFD-Online, this does not mean that I am now a "CFD expert". This on its own is not enough to learn all what needs to be learned... it only gave me the capability to overcome hurdles that also presented themselves at work, because learning how to do/use CFD is a lifetime experience and some details can only be learned by studying books and being taught by the experts themselves, in live sessions or webinars, not simply on a forum or a mere wiki page or two.


3. To feel accomplished

Tons of self-help books will tell this in one way or another: to gradually feel better about yourself, you need to solve one small task at a time. Then once you feel accomplished with that task, you take another step to the next task. Let your brain emit the rewarding chemicals that make you feel good and better about yourself.

Which is also what video games can give you one way or another: feel achievements were attained whenever you overcome artificial hurdles. And if you do like playing video games, then you can think that by helping others in real life you are earning Karma points in your real life... and reaching higher experience levels faster than just by doing things on your own.

But do not chew more than your mouth can handle... which you will also only be able to diagnose if you try things for yourself, otherwise you will not know how small should be the tasks that you can do or not.

That said, always challenge yourself and learn what are your limits and study how to overcome them. Although, you know, this is something you were meant to be taught in school since the beginning...


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However, as I've learned over the years: I can't solve everything nor reach everyone. I'm only one person and the funny thing is that even if I were to abuse time traveling technologies in the current Earth time line, I would not survive in my own time line enough years to help everyone.
So please, if you can find the time and if you have reached this part of this long blog post, please do your best to also help others. Even if it doesn't look like it, the experience you will gain from it can eventually benefit you.