Watched pot never boils

 Universal Law of Burner Attention:

The amount of attention paid to a gas burner on which one is making tea is inversely proportional to the amount of heating received by the cooking pot.

Simply put:

Paying attention to a gas burner leads to no heat reaching the vessel.

Corollary to the Law of Burner Attention:

When you look away for one split second, the tea on the burner boils over.

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