Expert systems are used to "mine" a large database. You ask an expert system things like.
How many units should I produce for these areas..
What is the best site for my store front.
Estimate profit and loss for the next two years..
The problem with expert systems is that they need data and lots of it to work well. The are no cheap databases available with the type of information required for a good expert system.
IF you could get all the data collected by the hundreds of thousands of business, on every aspect of their business, put into one database then maybe you could get a good expert system to use in a successfully way.
Your best bet for the moment is to get a good manager or do a business course..
Human intelligence is far superior to any AI system in existence.