Why can't they make a thermostat that can keep the house at a constant temperature?

Why can't they make a thermostat that can keep the house at a constant temperature?

Someone asked me this question, and I live this reality every day. Let’s look at what’s involved! Each room in the house has its own thermal loss and gain. To simplify, this is directly related to the difference between the indoor and outdoor temperatures. This is mostly true but other effects like sun shining, people,…

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