It is harder to achieve spirirual success because it requires much more mindpower and patience, although it is hard to say because material success requires luck and determination. To gain material success, someone must have a goal and plan on how they plan to achieve that success, along with having perseverance to get through and/or bypass any bumps in the road. Spiritual success does require a goal and plan too, but you really must stick to it and be patient enough to endure different situations and hard times in life, all while staying calm with no temptation and just your goal in mind. Someone wanting to be a billionaire vs. someone who wants to achieve enlightenment or open their third eye is not that easy to compare, it depends on what the person believes in, and what type of person they are. overall, I would say they're both pretty hard, but spiritual success is more difficult.
