Investors expect a reasonably high return on the risk capital (s)they employed for their buying/selling decisions of any financial instruments, whereas traders simply expect a reasonably highER return than most/general investors do.
Traders expect a return on the price changes of upcoming movements, whereas investors expect a return after longer-term movements.
This reminds me of the old joke about whether or not a woman is a hooker. If the "investor" ever sells his shares, he's a trader. The only difference is the amount of time the shares are held.