I think it is probably different for every business.
Business people are coming at it from a different place than accounting people, there are certain things they want out of it, and they are looking at it from a broader perspective than accountants are.
Accountants are typically thinking about preparing financials, making sure taxes get paid, etc, but business people are also concerned with compliance, having audits done, keeping track of their inventory, periodic maintenance on equipment, looking at information to help them create business strategies, planning, budgeting, and a whole host of other products that they may or may not get directly from accountants.
Because of this, business people often kluge together accounting systems with a wide variety of products and do their best to glue them all together instead of going out to buy a single package that does it all. They might, for example, use simple spreadsheets to keep track of assets, and create columns with their depreciation numbers, and then expect to close those numbers out to a control account at the end of the accounting period without storing any of it in their accounting software. They might have an asset management system in place that does bar coding, etc, and have that glued in some way to the system they use to pay their personal property taxes, again possibly bypassing their accounting software completely. They might have a completely manual time card system, or even a time clock, or it might be computerized and tied into their door entry system, and that might bypass the accounting software. Business people might be using a credit card processing system their bank sold them on that uses the bank's own software products to process and manage CC transactions, again bypassing the accounting software.
The point is, I think its really important to understand what accounting software is doing, to really understand double entry accounting, keeping journals, etc, because inevitably a business is going to be doing at least some of their accounting in a unique way, or with spreadsheets, or even written on paper, and the person doing the books is going to have to know how to bring that into the books, close it out at the end of the accounting period, etc, and keep it all straight. Someone who only knows how to use Quickbooks to do invoicing, for example, is probably going to get a little frustrated when they find out that the business is using an invoicing system from the 1940's because great aunt Barbara never learned to type and doesn't want to change the form she learned on when she was a teenager.
That from someone (me) who doesn't actually know that much about accounting, I'm still learning.
Edit, I thought of a good example of this. Pretend the business occasionally makes loans. It isn't the primary business, its just something the business does on rare occasions and they have a favorite piece of software that they use for this purpose that calculates the amounts due every month, creates bills to send out to the few borrowers they have to service, etc. They like their system, but it's not part of whatever accounting system they use to keep the books. You still have to know how the books work because your financials are going to be messed up if you can't figure out how to get interest income in, account for the loans themselves, and have some way to write off bad debt if someone defaults - the only way is to know how that is done manually and then figure out how to make it work in the computerized system.
