Why don't people use their Android devices?

Here's something which I've been curious about for a while now. Why don't people use their Android devices?

Android has a huge market share advantage in terms of devices shipped. But Apple's iOS devices are what people actually use. I've only got iOS devices, so I have some idea why I use my iOS devices heaps. (They work, and they are beautifully designed so it's generally a pleasant experience.)

But are Android devices really so rubbish? I've seen a few Android phones and from my brief look at them they seem less usable, and the apps seem less attractive to use. And I've seen a few videos on the web showing some of the more spectacular UI Android fails, which I guess must make using the phones more frustrating. Perhaps that frustration builds up?

The thing I don't get is that people don't even seem to do web browsing on their Androids, especially tablets (90% iOS, less than 5% Android). Have Google really made a web browser that sucks? Or is it that the better screens on Apple's devices do actually make a significant difference to usage?

And why would Android users be so much less likely to buy things? A recent example is TNW's tablet magazine:

To give you some insight in how little uptake we saw on Android here are some statistics: for every Android user that downloads an Android magazine we have 80 iOS downloads. (TNW)

Whatever the reasons are (and I'm genuinely mystified!), as long as people love actually using iOS devices, they'll keep making the bulk of the money in the market.