We diversify our investments by investing in different coins so that if the price of one coin goes down then we can cope up with it from our investments in another coin.I totally agree with you that if the investor has a small capital then how he can diversify his investments? If he will try to diversify his investments with a small capital then he will be able to invest a very little amount in every coin.But I think that it will be a more better choice than investing everything in one coin.It will be more safe and more profitable.