Credibility is not comprehension
A wall of famous logos can tell visitors that serious companies trust you. It cannot tell them what those companies hired you to do. When the offer is unclear, proof creates prestige without understanding.
The same is true of large percentages. A 40% improvement sounds valuable, but not if the visitor cannot identify what changed, for whom, or through which product.
Attach evidence to the claim
Place proof close to the promise it validates. A retention claim needs a retention result. A speed claim needs a before-and-after time. A product-mechanism claim needs something that demonstrates the mechanism working.
The visitor should never have to guess which sentence a testimonial, statistic, or logo is supposed to make believable.
Explain first, amplify second
The useful order is simple: make a precise claim, show how the product creates the result, then present the strongest relevant evidence. Proof is an amplifier. If the underlying signal is foggy, amplification produces louder fog.