I've got some advanced wizards with 30-35% accuracy provided by their gear, and when added to their base accuracy, those wizards have over 105%. They need to go about 5% beyond 'perfect' because some crafted and level 108 spells have slightly lower accuracy than normal. With such a high amount, they never fizzle ... unless they get hit with a smokescreen.
It's possible for a Storm to get 100% accuracy by level 45-50, as long as they have great gear and a helpful pet. Ironically, in the end game it's Ice and Myth who end up struggling the most with low accuracy - they have the hardest time scraping together that last 20%-25% from their gear.
What is the max accuracy or is 100% obtainable and you will never fizzle.
There is no max accuracy, and most people try to obtain at least the minimum requirement needed so they never have to worry about fizzling. For example, Life spells have 90% accuracy, so you just need 10% Life accuracy to ensure that you never fizzle.
However, most people try to obtain more accuracy than that. If a person has a total of 130% accuracy when choosing a card and they have a -45% accuracy debuff on them, then the spell will have an 85% chance of not fizzling (130 - 45 = 85).