[robbles]

The phrase "steep learning curve" is probably a misnomer, since the graph most people are talking about has "learning" or "experience" on the dependent axis, and time on the independent axis. So a steep slope on a graph like this would represent something that's very easy to learn.

What most people seem to refer to with this phrase, however, is some kind of exponential function, where the slope is really small (difficult to learn) at the start, and hopefully increases as you get past the initial hurdle.

I guess it stems from confusion with other real-world metaphors, like climbing steep hills, which also happens to be difficult.