If I can walk up to a light switch and flip it to change the state, it’s not smart, it’s a broken design.
But how does this apply to a smart home? If we think about the kinds of things we can add some intelligence to, lights are a common starting point but are also an easy way to break expected design. If I can walk up to a light switch and flip it to change the state, it’s not smart, it’s a broken design.