So for those who suggested using a state machine, why would it be a better choice, I mean in my case? Code readability and maintenance?
I know that when the execution of a certain task depends on the outcome of another task (and there are multiple states involved), then state machines are designed for that.
But in my case, once the user selects the data files, then ALL of the following steps must be done irrespective of the previous state.
1. table summary - placed on page 2 of my tab control container
2. type A plots - placed on page 3
2. type B plots - on page 4
4. type C plots - on page 5
5. Output the table and plots into ppt.
What is wrong with a flat sequence? what is the appropriate use of a flat sequence? I know someone must be thinking "flat sequence = amateur, state machine = pro 
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