Having anything in cache allows you to check for errors and requirements.
So for example if you're going to be away for 7 days and you need to spend $100 a day in notes, you might be able to avoid hitting a withdrawal limit, eg if you bank for some reason limits your weekly to $500.
Basically the estimate serves as an input into your requirements for the next step, and tells you whether there's something to worry about.
Same as if you're painting your house and you need to know whether you need to go buy a new bucket of paint or the existing one will do.
So for example if you're going to be away for 7 days and you need to spend $100 a day in notes, you might be able to avoid hitting a withdrawal limit, eg if you bank for some reason limits your weekly to $500.
Basically the estimate serves as an input into your requirements for the next step, and tells you whether there's something to worry about.
Same as if you're painting your house and you need to know whether you need to go buy a new bucket of paint or the existing one will do.