Lululemon shares are tumbling after the company said revenue would be lower than expected.

While the crash took some by surprise, insiders have seen a Lululemon implosion coming for a long time.

Last year, equity firm The Oxen Group called Lululemon's shares "strongly overvalued." Popular blogger LuluAddict wrote that former CEO Christine Day had ruined "everything special" about the retailer.

There's a lot going wrong at Lululemon, but here are a few major factors that led to the current predicament.