Term: Attribute Boost
An attribute boost normally increases a score’s value by 1, up to a natural/unmodified +10. At 1st level, a character can never have any ability score that’s higher than +4, except for in certain circumstances (such as with the Ancestry Talent "Hyperdiversity").
Player characters gain 1 Attribute Boost every even level (2nd, 4th, 6th, etc) via Character Progression.