These stocks are on a growth path that could go on for decades.Investors often act with the intent of never selling. Warren Buffett has often said that his favorite holding period is "forever," and holding some stocks for years or decades has often paid off for investors.Unfortunately, changing business conditions or management teams can make selling a stock the only wise choice, but one cannot truly make a promise to "never" sell.Nonetheless, I own stocks I cannot envision myself selling, and Shopify (SHOP ...