"Which channel do we start with?" is a wrongly framed question. A channel doesn't produce results on its own; it depends on the ideal customer (ICP) and the product. The right question: where does my buyer spend time, and how long do they need to decide?
The channel depends on the product
A simple, cheap product needs a fast decision — Meta (Instagram/Facebook) works well at the sales stage. A complex B2B product (ERP, SaaS) isn't sold with one ad: trust is needed first — YouTube (VSL, tutorials), content, LinkedIn. Here the channel serves as a staircase from awareness to sale.
"Let's be everywhere" is the most expensive mistake
At the start, focus on one or two channels. If you spread budget across five platforms, none accumulates enough data and optimization becomes impossible. Get to a result on one channel, then expand.