As a result of this question I have read some articles about Alexa and its wake-words. One of the articles mentions the following:
Finally, for people with multiple Echo units, there’s an argument to be made for multiple wake words. The microphone array on the Echo and Echo Dot units is very sensitive. If you have an Echo in your living room and a Dot upstairs in your bedroom, there’s a good chance that issuing a command to Alexa while standing in the foyer will trigger both units. In such instances, it’s really handy to have one wake word for the downstairs unit and one wake word for the upstairs unit.
Now it says that:
The microphone array on the Echo and Echo Dot units is very sensitive. If you have an Echo in your living room and a Dot upstairs in your bedroom, there’s a good chance that issuing a command to Alexa while standing in the foyer will trigger both units.
So then why would I need more of them when one can cover an average home? What are the possible use-cases that reasons having multiple Alexas at home?
Also to extend coverage it could be enough to use a simple wireless microphone unit connected to Alexa.