That's because it's not taught correctly. It's supposed to apply to words that have an "ee" sound from blended vowels, because those are the words that are confusing to remember whether the i or the e comes first. And even then there are exceptions (weird, seize, Keith). It was never meant to cover words with an "ay" sound like weigh or where the 2 vowels are pronounced separately (science, glacier, being).
But it's much more fun to pick words that "disprove" the rule for Internet points (even though they were never meant to be in scope).