She is a perfectionist who always strives for the best.
Она перфекционист, которая всегда стремится к лучшему.
Definitionen
A person who refuses to accept any standard short of perfection.
As a perfectionist, she spent hours revising her report until it was flawless.
An adherent of the doctrine of perfectionism, especially within certain Christian movements that advocate the attainment of moral or spiritual perfection in this life.
Nineteenth-century perfectionists believed that complete holiness was achievable on earth.