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Shouldn't you pay for it or return it once the coding process is done?
Do you sort of understand where I am coming from?
No I don't - because you are not comparing similar environments.
If they were to employ someone to write the software from scratch the cost would certainly be well above handing out some boards to developers. Then of course there is the support of that software for eternity until the Avalon boards are considered no longer worth supporting.
By having developers support their hardware they gain more sales.
Why should developers do the development and support for them for free when they are purely profit driven themselves?
In the larger world of linux kernel development for example, when developing original novel code for new hardware all we need to do is ask the manufacturers nicely for some sample hardware and provided the developer is a known developer for code in the past they are often given samples of hardware that isn't even available for sale yet. This is always going on with the manufacturing from Intel, AMD, IBM etc. They are aware that having software available for their hardware is only beneficial to their hardware sales and the cost of sponsoring the software development directly versus giving away a few hardware samples is a simple equation that works in their favour. Indeed the developers are often invited to pre-release talks from the manufacturers regarding the hardware development and their input valued and can often change hardware development direction before release because these are the people who know what they're talking about and the manufacturers realised this long ago. Great hardware is only ever made when the software developers are involved in the development process and the software that goes with it is shipped at the same time.
Thinking us software developers just want "freebies" is just a short sighted view of the world. It's only on this round of bitcoin hardware development (with ASICs) that the manufacturers have even begun to embrace what the massive manufacturers have been doing for years, and not remotely on the scale that Intel and AMD would since we're largely in the dark about the hardware and communication protocols until virtually the release date. Of course the scale, timelines and profit margins are completely different, but the variables remain the same.
EDIT: Trust me, you don't want to actually contract me to do software work. It's prohibitively expensive - just ask coinlab who did contract me. Or, you can rely on me coding free software instead.