Excel is helpful in running a business because it will help you keep everything in order, you wont lose anything. Changing the values would affect business decisions because everything will either change by increasing or decreasing.
Some problems that we would have would be that the spreadsheet would be bigger than the screen so you would not be able to see like the columns and some cells. This would be a problem because you would have to move the scroll bar which would take more time to do than just look at it. Also because if you are not able to see the row titles then you won't know what the information is referring to.