At a Python conference many years ago, around the year 2000, Eric Raymond gave a keynote. This was when his "The Cathedral and the Bazaar" was widely discussed, and he was pushing the then new term "open source".
He used as an analogy how you can go to <fancy restaurant>, taste something amazing, and ask for and get the recipe. Yet even though you could make it yourself, you'll still visit the restaurant because they have the skills and practice to make it more easily than you could.
By analogy, he argued, even if you release under an open source license, you'll still get people hiring your services because that's more effective.
Someone in the audience objected. He pointed out that he had worked at <fancy restaurant>, that the recipes deliberately omitted detail, and that staff had to sign an NDA - it was nothing like "open source".
I already had my doubts about Raymond's understanding of things. That was the final nail.
One example of this is that Brewdog release quantities and precise instructions and notes so that enthusiasts can homebrew their favourite beers. I know because one of my colleagues spent a lot of money on computerised brewing gear and always has a homebrew or two in progress because he likes experimenting and tweaking things slightly.
But these people also still go to the pub to drink them on a night out or buy them in a can from time to time. The truth is that it's actually a lot of hassle to do homebrew well so that it tastes consistently good, and even ignoring the expensive equipment my friend has, he still probably pays more per pint to brew his own than just buying it pre-made. Obviously, he does both because he enjoys the process.
He used as an analogy how you can go to <fancy restaurant>, taste something amazing, and ask for and get the recipe. Yet even though you could make it yourself, you'll still visit the restaurant because they have the skills and practice to make it more easily than you could.
By analogy, he argued, even if you release under an open source license, you'll still get people hiring your services because that's more effective.
Someone in the audience objected. He pointed out that he had worked at <fancy restaurant>, that the recipes deliberately omitted detail, and that staff had to sign an NDA - it was nothing like "open source".
I already had my doubts about Raymond's understanding of things. That was the final nail.