Years ago, my wife did some contracting work for a team responsible for the voice assistant at one of the major tech companies. Her role required her to work with the directors and VPs and she came home one day to tell me how one of them laid out their grand vision for the product and was talking about how, not only will people use these things to buy every day items, but one day people will be making major purchases like cars with these things.

I can't speak for the Alexa team, but if the execs at Amazon are anywhere close to that delusional, it's no wonder these things are falling short of expectations.

The problem IMO is trust. These devices get simple commands like, "turn off the lights" wrong on a semi-regular basis. No one is going to trust Alexa to buy the right thing until they're confident that it consistently understands them correctly and currently the error rate is just too high. Even if it does understand me, I don't trust Amazon to send me a quality product.