There can be several reasons for a business to change its chart of accounts. One reason for changing the chart of accounts is to better match how the business is organized. Perhaps the chart of accounts was established when the business was much smaller (fewer products, fewer customers, fewer managers). Now the company's more sophisticated operations require more detailed reporting that is segmented by processes and/or by each manager's area of responsibility.
Another reason for changing the chart of accounts is a company's decision to acquire and install a new computerized system for controlling its operations. The new system's general ledger might result in a chart of accounts which is different from the previous chart of accounts.