You're comparing apples and monkey nuts. One of them is good for eating, one of them is not. It's a logical fallacy.
Combee is a basic Pokemon, of which the females of the species evolve into a UU Pokemon. UUs tend to generally be underpowered in OU in the first place, and Vespiquen is not a remarkable Pokemon. The NFE, Combee, will most likely do far worse than Vespiquen because of its lower base stats, among other reasons. The NFE Combee's base stats are also lower in almost every category spare speed than that of Spinda.
Spinda is a Fully-Evolved Pokemon, and it's stats are generally better in every category. You can't compare the two, particularly because the mentioned Combee would be playing in a tier outside of even it's fully-evolved form, while Spinda is a UU Pokemon.