Budget Mistakes

Starting with daily budgets too low to exit learning phase — platforms need 50+ conversions/week per ad set to optimize properly
Spreading budget across too many campaigns early — concentrate spend to gather statistically significant data faster
Killing ads before statistical significance — minimum 100 clicks or 1000 impressions before judging creative performance
No contingency for scaling — reserve 20-30% of budget for doubling down on winners mid-month
Treating ad spend as expense, not investment — track payback period, not just immediate ROAS

Metric Traps

Optimizing for CTR instead of conversion — high CTR with low conversion = curiosity clicks that waste budget
Trusting platform-reported conversions — attribution windows vary (7-day click, 1-day view), always cross-reference with actual revenue
Ignoring frequency — above 3-4 frequency per week, performance degrades and audience burns out
CPA tunnel vision — a $50 CPA is better than $30 CPA if LTV is 3x higher for the $50 cohort
Vanity reach metrics — 1M impressions mean nothing if 0 target customers saw the ad