The x axis is "complexity of website" and the y axis varies. For the red line that slopes from top left down to bottom the y axis is "demand for website". The blue line is "Cost of website produced by web developer". Everything to the left of the vertical green line has a tool (wix, squarespace, wordpress etc) that makes it easy to produce that type of website. And over time that green line moves along the x-axis complexity scale. But the green line will only go so far, because you can't justify handling increasing complexity with a decreasing demand indefinitely.
Also, at some point it becomes easier to hire a web dev to make you a custom ecommerce solution, than to search through the 500 ecommerce solutions to find the one you want, when what you want is weird.
My strategy since 2006 has been to stay to the right of the green line, but not too far. My experience is that clients I've had on the right side of that line are still clients, and those who were not, have moved on.
I think there's a lot of legs left in that strategy. Finding a client who is on the right hand side of the line often means starting with some kind of integration work they are struggling with, or updating a legacy web app, which is always a pain. Or doing something weird. But once you've got through that successfully you're established as a meaningful cog in their corporate machine.
Interestingly, I drew the graph in 2006, and wix was founded that year, and was one of the examples I used at that time, so it's funny to see it still being mentioned now.
The strategy has given me a varied set of problems, I've worked on custom ecommerce solutions, funding application and claim management systems, CPD management, eLearning tools, and other more mundane things.
I've earned more each year I've been doing this, and it jumped up a couple of years ago, so it's still working well for me.
My business grew organically, with introductions from friends, old colleagues and distant family. So there were calls at the beginning. Now my business number goes straight to voicemail, and important clients get to call my mobile. So the answer is that I don't do marketing and sales so to speak, I do quotes, so I suppose that should be included. That accounts for less than a day a month.