> Given purchasing power scale and people like fast delivery there will only be a handful of companies that can complete with Amazon ever, so it seems unlikely there will be a 'started in the garage' business compete with them now the market is maturing.

I'd rather just walk into Target (same day pickup), Walmart (same day pickup), Best Buy (who price matches), B&H, Buy Buy Baby, Home Depot (same day pickup), Bed Bath & Beyond, or Kohls. I can't buy clothing online because I'm not willing for it to take a week to try something on, ship it back if it doesn't fit, get a different size in the mail, etc. The few bucks more at a physical store is worth it to have the size that fits today. I'm not willing to buy human consumables worried that they're counterfeit from an unscrupulous third party seller I will have no recourse against. I have to go to the Apple store for anything Apple related because I can't trust Amazon's reviews or their supply chain that what I'm receiving isn't a Chinese knock off that is out of spec. I buy SD cards and USB flash drives from Walmart because I don't trust I'll receive an authentic version from Amazon (having received many in the past that did not match advertised capacity).

I won't even buy baby formula from Amazon; I buy direct from the manufacturer, and it takes 3-4 days to get to us (cheaper than worrying its counterfeit). The horror of having to wait an extra day or two and plan ahead!

ashelmire's sibling comment hits the nail on the head: I do not trust Amazon anymore (without even touching on their labor practices). The UX is still great for me to track down products I might like or need and then go shop for them in person.