Here's why:
* The vowel sound in "repeat" is a short "e" sound. It's the same sound as the "e" in "pet" or "bed."
* Long vowel sounds are typically associated with a single vowel letter followed by a silent "e" at the end of the word. For example, "late," "hope," or "kite."
Therefore, the "ea" in "repeat" does not represent a long vowel sound. It represents the short "e" sound.