Why can't I tell which channel is driving revenue?

If you've ever added up the conversions your channels reported and gotten a number bigger than your real sales, you've met the problem directly. It isn't that your tools are broken. It's that each one is designed to take credit. Fixing it isn't about buying a better tool. It's about deciding who gets to keep score.

Why do the numbers add up to more sales than I made?

Because a single buyer touches several channels on the way to becoming a customer: they click an ad, come back through search, then convert from an email. Each platform sees its own touch and claims the whole sale. Three platforms, one customer, three reported conversions. Multiply that across a month and your dashboards describe a business three times the size of the one you actually run.

How do I fix it without expensive software?

Take scorekeeping away from the players. Three moves do it:

• Pick one source of truth. Your CRM, backed by GA4, not each ad platform's self-report. One system decides what counts as a conversion, and it's the one that also knows about revenue.
• Separate revenue channels from activity channels. Some channels produce customers; some produce motion that looks like progress. Grade them differently instead of averaging them together.
• Weight conversions by deal value. A $500 client and a $50,000 client are not one conversion each. Once you weight by revenue, the channel that looked like your winner on volume often turns out to be your loser on value.

Do I actually need attribution software?

Not early. For most B2B services firms, a CRM with clean source tracking plus GA4 answers the revenue question honestly. Dedicated attribution software earns its price only once you have enough volume across enough channels that the modeling changes a real decision. Buying it before then just gives you a more expensive version of the same double-counting. This is the difference between capturing demand and creating it too. You can't tell which channels create versus merely catch until you keep score in one place.