The Globe and Mail reports in its Friday edition that passing on a stock purchase just because the price has run up can be a costly mistake. Guest columnist Gordon Pape writes that sometimes it is the right call, and sometimes it is not. When he first recommended Amazon in January, 2017, the shares were trading at $817.14, with a trailing 12-month price/earnings ratio of 182.80 (all figures U.S.). Five years earlier, the shares could have been purchased for about $200. After a 20:1 stock split, resulting in an adjusted book price of $40.86, Amazon closed June 17 at $214.82. That was a profit of 426 per cent since the original recommendation. Nvidia is another example. The wise Mr. Pape advised buying shares in May, 2021, at a split-adjusted price of $16.24. At the time, he noted that the shares were already up more than 200 per cent year-to-date and had a PE of 94.17. But the company had a virtual monopoly in producing the computer chips needed for artificial intelligence, so he advised readers to buy. Nvidia currently trades at $144.12 for a profit of 787 per cent since he added it to his newsletter's recommended list. All this is to point out that when a stock goes on a run, the trend can continue for a long time.