Shares in the largest UK companies, for example, are highly marketable. Many other shares have reasonable marketability. However, shares in smaller companies have poor marketability. Investment in unmarketable shares should therefore be seen as part of a long term investment strategy. Lack of marketability therefore restricts the potential for profits from active trading.
Market values can be very volatile.
The more volatile the share price, the less secure the capital value of the investment, and vice versa. Movement of the worldwide equity markets. The whole market moves up or down in response to global news or views. News about a particular industrial group affects the share price of companies in that industry. An example is the period when all companies in a sector report good or bad results.