a word about language: the learning curve

At work, I was talking to someone about a new project I'll be taking on. It was noted that there would be a steep learning curve.

The meaning of that expression, as everyone knows, is that it would be difficult to learn what's needed. I suppose the expression came about because it's hard to climb a steep hill. So, steep learning curve means hard to learn. But that always sounds wrong to me. If the learning curve is a graph showing how much is learned over how much time, a steep learning curve means that a lot is learned quickly, which seems to imply that the subject is easy to learn.

So, guess what I found? I did a Google search to find an image to include with this post -- while I have no data to back me up, I am willing to bet that including a  graphic makes it more likely that people browsing this blog will stop and read. And I found a site that seems to agree with me.

I have no experience with that website, but the author made the same point as I did above. Only she made it better, and seems to imply that in technical fields, the concept of "learning curve" is handled the way I instinctively think of it. To quote:

The typical plotting of a learning curve shows the time (or experience) for learning on the x axis and the percentage of learning on the y axis. In science (and contrary to popular usage of the term) a steep learning curve represents a quickly-learned subject. Difficult subjects will have a longer duration to complete learning and, as such, a shallower curve. The relative percentage of learning can show how some subjects can be mostly learned quickly while some difficult aspects may remain resulting in plateaus in the graph where learning stalls. 

Now try convincing the world of that.