If your garlic did not grow any scapes the most likely reason is that it is a softneck variety, and softneck garlic doesn’t grow scapes. If you are sure your variety is a hardneck variety that should grow scapes, the reason might be late planting (such as spring planting) and a not long enough growing season, or the scapes might simply be delayed due to weather and growing conditions, and you might just need to wait a bit longer to see your scapes appear.