Board Thread:False Info and Speculative Discussion/@comment-24732895-20170731171934/@comment-4723271-20170802185651

Deaton could've just said it was rare, but he didn't. He specified. I know a True Alpha isn't gong to appear every 100 years exactly. But there's still no chance of Liam being a True Alpha. If it were as simple as being a decent 16 year old werewolf, then True Alphas wouldn't be as special as they claim them to be.

Scott became an Alpha in S3. Liam became a werewolf in S4. You essentially just jumped from 100 years to a few months (give or take) between true alphas.