I'm new to D&D. There seems to be a discrepancy between the 5e Starter Set Rulebook and the associated character sheets. The Rulebook says that a passive wisdom (percep) score is "10 + the creature's wisdom modifier, as well as any bonuses."
In the example they have a 1st-level character (with a proficiency bonus of +2) Wisdom of 15 (+2) and a proficiency in Perception, he or she has a passive Wisdom (Perception) of 14 (10+2+2).
But the Human Fighter Folk hero character has a WIS mod of +1, and a +3 written beside perception, and a passive Wis percep of 13 (not 14?).
The Dwarven Cleric has Wis mod of +3 and a +3 written beside perception, and only a 13 passive wisdom.
I guess this has to do with proficiency in the skill, but I'm confused. Can someone explain these instances and maybe also when proficiency is used, vs when just the modifier or just the skill without proficiency?