Understanding your numbers Why ROAS is the most misleading metric in B2B marketing
Every ad platform reports a number that makes your ad spend look like the best investment in your business. Google calls it ROAS. Meta calls it Return on Ad Spend. The number is almost always higher than your true marketing efficiency because it only counts ad spend in the denominator and uses attribution models designed to claim credit for as many sales as possible.
A B2B business reporting a 6x ROAS on Google Ads is telling you that for every dollar spent on Google, six dollars of revenue was attributed to Google. What it is not telling you is that the same sale was also attributed to Meta, that your marketing team costs $15,000 per month, and that your true marketing efficiency ratio is closer to 1.8x once every cost is included.
What ROAS does not count
Ad platform ROAS excludes: the salaries of everyone on your marketing team, your tools and software subscriptions, your agency and freelancer retainers, your content production costs, and any organic or referral revenue that was generated outside of paid channels. When you include these costs, the real return on your total marketing investment is typically 40 to 60 percent lower than the ROAS your ad platform reports.
The sum of all platform ROAS numbers across Google, Meta, and LinkedIn frequently exceeds total actual business revenue — because every platform claims credit for the same customer.
How MER gives you the true picture
Marketing Efficiency Ratio fixes both problems. By dividing total revenue by total marketing spend, MER cannot be inflated by selective attribution. It does not care which platform claims credit for a sale. It measures the output of the entire marketing system against the total input. A business with a true MER of 4x is generating four dollars of revenue for every dollar it spends on all marketing activity combined. That is a number you can make real business decisions with.
The MER benchmark that separates profitable from unprofitable growth
For most B2B businesses with gross margins between 50 and 70 percent, a MER of 3x is the approximate break-even point for marketing investment. Below 2x, you are likely spending more on marketing than the margin generated by that marketing can support. Above 5x, you have room to scale spend without destroying efficiency. The goal is not the highest possible MER — it is a MER that is high enough to be profitable and consistent enough to be predictable.