I disagree. Amateurs don't necessarily need pro tools, they need tools that help them do the job that they want to do better than either no tools, or poor tools. They also might get confused and put off by the steep learning curve offered by some pro tools. E.g. PhotoShop (I don't think I need to say more).

Just because something isn't a good fit for the pro or power user, doesn't mean that it doesn't have a place in the market, or couldn't be considered good or useful.

Really? I thought it sounded more like KISS and what Apple have been doing: Making software accessible to the (amateur) enduser. (E.g. the iWork and iLife suites as well as many iOS-apps)

Sure, some people might need advanced tools for their advanced workflows, but there's often a huge market in software for the everyday-man and -woman who only [writes] as a hobby.

It's not really. The point is that the market is segmented and you need to target the segment for which your product is the right fit. People who already have a fully-featured tool which solves their problem and they are comfortable with are never a good market.

It's not that they don't "know better", it's that their needs are different. Just like it's hard to sell an amateur tool to a professional, it's hard to sell a professional tool to an amateur.

Of course, that's not the only division. Small business vs. enterprise is another. For instance, Amazon S3 enabled an entire new class of content-based web startup. Not because it was "like having fileservers but worse", but because it served the needs of users who needed to host files, but didn't need and couldn't afford to have their own hardware. A group which was otherwise underserved in the market at the time.