Spent two weeks on performance for a client site. LCP from 3.4s to 1.6s, CLS basically zero, all green.
Conversion rate change: +3.1%. Statistically real, commercially underwhelming for two weeks of work.
Not saying performance does not matter. Saying that if your conversion rate is bad, it is probably not your LCP, and the performance work is a comfortable thing to do instead of the uncomfortable thing, which is fixing your offer.
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