Tell that to all the brands who have both a logo and a mascot, especially those whose mascot does not appear as part of the logo or only selectively appears alongside it. Geico, Progressive, Pillsbury, Planters, M&Ms, Ronald before he was discontinued, etc. And somehow Adidas has like four logos (all with recognizable silhouettes and with good use of negative space!) and they haven't tanked yet.

None. I grew up surrounded by mascots.