Why does height not fit the long I rule?

Answer 1

Most words that have the EI pair give it a long E sound (receive) or a long A when it is used with the silent GH (weigh, eight). The words height are sleight are among the few words where EI has a long I sound.

Answer 2

The "long I" rule typically applies to words where the vowel is followed by a consonant and then another vowel (e.g., like in the word "time"). The word "height" does not follow this pattern as the "i" is followed by a combination of consonants ("gh").