Every purchasing decision involves a trade-off between what I call fidelity and convenience. Fidelity is the total experience of something - how great the experience is. Convenience is how easy it is to get something. A live concert is a high fidelity way to experience music; an MP3 file is a high convenience way to experience music. Depending on the situation, one or the other is probably pretty appealing. What's not appealing is something that offers neither.

Some of what we're learning suggests a balance between exposing children to new things, yet giving them a chance to repeatedly experience something they enjoy, which builds "chunks" of information in their brains.

Fidelity is the total quality of an experience, including a sense of exclusiveness and aura. Convenience is simply how easy something is to get, which often means a low price and ubiquitousness. A super-fidelity product or service would lose its luster and quality if it's pushed too hard toward convenience. A super-convenient product or service would start to get expensive and exclusive if it moved toward higher fidelity, which would naturally undermine its convenience.

Chunking is the ability of the brain to learn from data you take in, without having to go back and access or think about all that data every time. As a kid learning how to ride a bike, for instance, you have to think about everything you're doing. You're brain is taking in all that data, and constantly putting it together, seeing patterns, and chunking them together at a higher level. So eventually, when you get on a bike, your brain doesn't have to think about how to ride a bike anymore. You've chunked bike riding.

The explosion of the Web and digital media from 1995 to 2000 shook companies more profoundly in a shorter time than anything since the end of World War II.

High fidelity is a rich experience, and you'll put up with terrible convenience to get it - maybe it's high cost, waiting in line, jumping through hoops. High convenience is the opposite - it's a commodity, but it's cheap and easy and ubiquitous. A great exclusive boutique shop is high fidelity; Wal-Mart is high convenience. Both are hard to establish in their own way. The thing to remember about sustaining either is that you can't sit still. Some other entity will always find a way to challenge your fidelity position or your convenience position.

A CD these days is not all that convenient, and it doesn't bring enough fidelity to make you put up with that inconvenience. So, nobody buys CDs anymore.