Will an atheist succeed in his quest.?
Since we do not know what their aim in life is all about.
An atheist can succeed in his quest if he/she is determined. It does not matter what the quest is, as long as he/she has determination. Anything in this world is achievable with hard work and dedication.
i Guess (with short comings )
Anybody can succeed in their quest if they are motivated enough. Religion has nothing to do with your goal, unless your goal is to convert people to atheism.