A question about nothing really. The principle is everything the same " buy low" and "sell high". There may confusions occur but I think making profit from speculations is intuitive and was clear even in middle ages. There is no other ways to make profit from trading apart from one you described and if anybody " buys high" it means they expect to see further growth. The trend is your friend so if you managed to identify one of them, the earlier you noticed the more pips grabbed. Easy as that.