system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: how does it take several minutes to get water to boil in a pot yet a Coffee maker can heat cold water to scalding hot in mere seconds ?
gpt
In a pot on the stove not all of the heat energy (either from the gas flame or the coil on an element) goes into the pot - you get a lot of that heat escaping around the sides of the pot. An in the case of an electric element, if your pot or element are worn and not perfectly flat/flush with one another, you're naturally imposing imperfect heat transfer. Then, you have to sink a lot of that heat into heating the pot itself before the water gets heated. 

Inside an electric kettle, the giant (aluminum?) heating element or coil is being fed electricity directly - i.e. its heat is coming from the resistive heating effect of the current flow running through it (or through an electrically isolated inner bit) - thermal flow from the element to the water is direct. Also its coiled to maximize surface area. Thus, 100% of the heat is being sent into the water that surrounds it. 

In a coffee maker, the heating element is relatively small, but super hot. It takes small drips of water from the reservoir and vaporizes it immediately; the steam travels up to the drip pan and condenses as hot water to drip through your coffee grounds. So in that case, its a very small but hot element vaporizing just very small amounts of water. 

In both latter cases because 100% of the heat is going to the water, its much more energy efficient and usually quicker.