It depends how you define "user-friendly", which is not as obvious as it seems. The question is who is the 'user' that it's friendly to? The power-user who use

It depends how you define "user-friendly", which is not as obvious as it seems. The question is who is the 'user' that it's friendly to? The power-user who uses an application every day where the initial learning curve will consist of a relatively small amount of time compared to the speed and frequency of doing tasks, or the new user who is likely to do something only once and as such will never get past any 'learning curve' and only the initial understanding matters? Is it "flawed" to intentionally develop something to focus on the prior but not the latter? Is it a fair trade-off to deliberately increase the learning curve for long-term flexibility and power? If the Unix terminal isn't to some degree "user-friendly" why is it rediscovered by successive generations who notice its speed, power and flexibility over the alternative GUI interfaces? When given a /free choice/, why does a certain subset of users /choose/ the terminal over the GUI interface?