Spell Fizzels

I have been playing a caster for a while, and I get different rules of what happens when you fail to cast the CTN of a spell.

On pg 141 of the main book it says: must pay the spell’s speed cost, suffer Stamina damage equal to double the Spell’s Strain.

While on pg.345 of the main book it says: Advance your Clock by 1 and gain Strain equal to the spell’s final Speed cost.

Which one is it, or is there a ruling I missed?

Thanks,
Confused Caster