Answer:
The government (the SEC) imposes several regulations on publicly traded corporations and requires mandatory reporting regarding their financial position, compensation to key employees, auditing and accounting procedures, conflicts of interest between upper management and shareholders, operating results, etc.
The pros of that large amount of reports is that it makes management accountable for what happens and it makes their job more transparent.
The downside is that they are expensive and time consuming.
On the other hand, privately held corporations decide what to disclose to the general public or the government. The IRS is something that cannot be avoided, but the SEC and its scrutiny is avoided.
Other advantages of publicly held corporations:
Other disadvantages of publicly held corporations: