By "fast investment" I believe you mean investing for quick gains, actually some people still invest for quick profit especially day traders, and it works for some. The most important thing is to make profit when it comes to altcoins, and convert profit to BTC in my opinion because most altcoins will fail in the long run, just few with real use cases and resilient team will stay for so long. Price action traders who are pro in technical analysis do invest for quick profit, it doesn't make any difference. Sometimes you still hold long term and at the end you lose, sometimes its favorable.