In this 5th ed, Rogers, recognizes that The Internet Changed Diffusion. So that's interesting; alas, the current edition is a decade old, so there are limits to how far that's been taken. Rogers emphasizes the social aspects of diffusion, which is one of those true-depending-on-definitions things.
I wish there was more about how innovation/adoption winds down. This is a problem I chronically have: not just, what was involved in the format becoming successful, but then how was it displaced/replaced/rendered irrelevant. Adoption curves that just show how VCRs _entered_ people's homes and lives, without documenting how those VCRs _exited_ people's homes and lives are missing a really important part of the story. He at least mentions it (Discontinuance).
I don't care for the language he uses to describe what people are thinking as they are contemplating an innovation. I don't think that's how most people think about whether or not to adopt/buy/change. "Will the innovation be beneficial to me in my particular situation?" It might be "true" in some sense of true, but people tend to adopt a technology from a very different place: "Everyone else is doing it." "My kids are demanding it, and I guess it's not that expensive." "I can't buy X anymore, and the replacement is apparently Y. Dammit. I guess I'll have to switch everything over now." Are they "benefiting"? I bet they'd argue with you. When people are excited about something new, it's also not clear they are thinking "will it be beneficial". They're usually sort of more, Ooh, Bright, Shiny, Cool! If they were thinking "will it be beneficial" "to me" in "my particular situation", then when I asked them questions that were more or less word for word along those lines, they'd fucking well have an answer. They don't think about it this way.
Rogers is framing this stuff the way the very earliest (and least successful) advertisers framed advertising: list the pros/problems solved. People will "get" it! (har de har har)
The myth of rational decision making! "five steps usually occur in .. sequence .. knowledge .. persuasion .. decision .. implementation .. confirmation". His example of out-of-order is someone being "ordered to adopt by some authority figure". Lots of people implement THEN acquire knowledge and are persuaded. This is classic replacement tech adoption: the old thing was discontinued and it then breaks or you can't buy inputs for it, so you have to buy a new thing, whether you want it or not. (But, honestly, you can construct examples of it with clothing, construction and agriculture in any century and civilization you care to name.) He does talk a bit about organizations making decisions versus individuals, but again, his example is authority driven, rather than a no-remaining-choice-in-the-market.
His description of a social system has a problem frame (which is problematic! Har de har har). Social system examples include Peruvian village, medical doctors in a hospital, consumers in the US. "All members cooperate at least to the extent of seeking to solve a common problem in order to reach a mutual goal. This sharing of a common objective binds the system together."
Bad frame! No biscuit! Look, I get the appeal; I'm a pattern matcher and problem solver myself. But wrong! Wrong wrong wronger than wrong!
*sigh* I will continue later; I'm going to go get lunch now.
Continuing: lunch was good. Love how Rogers describes different research traditions within diffusion research (good "self" insight applied at the level of the academic discipline and entirely appropriate). LOVE the story about Bali, Lansing and the attempt to replace the longstanding, temple managed water/pest control system with different kinds of rice as part of the Green Revolution. Obvs, really bad things happen and fortunately they were able to revert to the old system to recover and then Lansing shows up to understand what happened and why.