Why go public, then? Going public raises a great deal of money for the company in order for it to grow and expand. Private companies have many options to raise capital – such as borrowing, finding additional private investors, or by being acquired by another company. But, by far, the IPO option raises the largest sums of money for the company and its early investors.
Being publicly traded also opens many financial doors: Because of the increased scrutiny from analysts and investors, public companies can usually enjoy better (i.e. lower) interest rates when they issue debt. Moreover, as long as there is market demand, a public company can issue more stock in a so-called secondary offering. Thus, mergers and acquisitions are easier to arrange because stock can be issued as part of the deal.
For investors, trading in the open markets means liquidity. If you are a shareholder of a private company, it is very difficult to sell your shares, and even more difficult to value your shares. A public company trades on a stock market, with ready buyers and sellers and known price and transaction data. The stock market is therefore referred to as the secondary market, since investors are buying and selling stock from other public investors and not from the company itself. Public markets and liquidity also makes it possible for a company to implement benefits like employee stock ownership plans (ESOPs), which help to attract top talent.