Investopedia should not be your source of truth. While you can get quality education for free on the internet in various subjects(math, CS, biology) - financial

Investopedia should not be your source of truth. While you can get quality education for free on the internet in various subjects(math, CS, biology) - financial markets is not one of them. Market value is exactly what the parent asserted it is, and the source of truth for that is your bank. If you are long 500k shares of AAPL and the quote is $100 - your bank will not consider you to have $50mil liquid assets. They know(and you should to) that starting to unwind a position of that size will decrease the market value a considerable amount. Maybe an example will help you out here.... Let's walk through that AAPL example. You are sitting on 500k shares. Step 1: Order 100,000 shares sold at market. Step 2: Observe your average sale price is more likely to be $90-95 than $100. Step 3: Order another 100,000 shares sold at market. Step 4: Observe your average sale price is more likely $90-91 than $90-95. Steps after this: same result, diminishing prices resultant from your sale(s). See a trend here? The market value of your assets is decreasing based on the market's perception of value, not on the mechanical formula investopedia fed you. Your unloading of shares is going to decrease the perceived value, which decreases the price you can sell them for. tldr; investopedia's advice on markets is barely more accurate than urban dictionary's advice on word meaning.