Earlier quoted context omitted.
The purpose of stock markets is to find the "correct" price for a stock. To that end, it needs to be possible to express both bullish and bearish views. However, doing the latter is already more difficult because in order to short the stock, you need to borrow it first, and you need to pay for those borrowed shares for as long as you keep holding them. Furthermore, those borrows can be pulled at any time, forcing you…
>> The purpose of stock markets is to find the "correct" price for a stock. Is it? Who's purpose? The main purpose of an IPO is (was?) financing. IE, raising money for the company operations... like a bank loan, VC investment, etc. In practice, many of today's IPOs are companies that don't need to raise money (anymore). For those companies, their main purpose when doing an IPO is usually liquidity. IE, letting founde…
Investors (as opposed to speculators) and anyone interested in general economic efficiency.
After the IPO, a stock ultimately represents a claim on a future revenue stream, and as such the "proper value" would be the (proportional) NPV of the company's future income. To the extent the market price doesn't reflect this, it represents inefficient allocation of investment resources.
Unlike bonds, an equity's future income is very hard to predict, so providing that pricing information, along with liquidity, is what ostensibly distinguishes Wall Street from a casino.
Personally, I don't care about short selling. I trace the root of the problem to the fact that dividends are taxed much more harshly than capital gains because capital gains don't incur taxes until sale, so they compound better. This incentivizes mature companies to retain earnings and grow through M&A (including of competitors), leading to this glorious present of megaconglomerates and oligopolies we are now living in. My prescription would be to incentivize dividends and discourage retained earnings so that some connection to reality is re-established in the market.
Another of the many problems with megaconglomerates, aside from them being anticompetitive, is that it is much harder to accurately predict the combined future income of 100 aggregated businesses than just one, so their very existence distorts prices all the more.