You may not have thought much about your competition or outsourcing some of your work, but things like that will impact your ability to make a profit. And you will find this especially so in the beginning phases of your business. Even you are just opening a lemonade stand in the front yard, you will still need to know what Susie is selling her lemonade for on the next street over!
Now, in addition, when you know the average number of transactions per customer and you know your average dollar sale per transaction, you can also project how many customers you would need over those 10 years as well. This would tell you everything about what your business would need to do to give you the salary you want. So, wouldn't it be nice to see what a plan like this would look like? Could you do it? It might not be as tough as you might think.