Axioms are chosen so that they are evident a priori Wonder why it took 2000 years to came up with alternatives to the 5th postulate, if all three variants (Euc

Axioms are chosen so that they are evident a priori Wonder why it took 2000 years to came up with alternatives to the 5th postulate, if all three variants (Euclidean, elliptic, hyperbolic) is so evident apriori?