One marketing channel might be sufficient to get traction in sales. There might be a need to try most or some of the channels to find the one which works for your products or services. For someone, it might be referral marketing like in the case of DropBox. For someone, content marketing might work like in the case of Reddit. The aim of marketing should be to find the right platform for your organization. Keep your marketing plan open for new channels too besides the traditional channels. Once the right channel is traced, the world is yours!