Just a nugget.
A business idea without proper management plan is one that can be considered to be dead on arrival. Business success revolves around excellent management plan first before capital size. With a large capital chunk into any business that's lacking in proper planning, such business can inevitably collapse, turning into a wasted investment.
But on account of proper management structure on ground with even the small size of capital, it can be sustaining to such business's success in the long ... Experience should be considered as a key asset in business planning and as a key factor it's important to always involve those with experience in the area of business when planning. Never neglect this!
I agree with everything you said. But based on my experience, I also know that there are many factors that cannot be planned.
Especially, similar or even identical planning structures can yield very different results in different times, different periods.
And sometimes, there’s no way of knowing these time related differences in advance.