Meaning if that sensor ever fails and starts giving bad data, the MCAS will misbehave, by its very design.
The MCAS system is probably behind the two recent crashes of the new Boeing 737 Max 8 that killed a total of 346 people.
Pilots complained after the first crash that they havent even been made aware of the existence of the MCAS, let alone being informed by Boeing in detail about how to handle it.
"Bei der Boeing 737-Max hat mich ja umgehauen, dass MCAS nur an einen der beiden Anstellwinkelsensoren angeschlossen ist. Leute, die so was vorschlagen, planen, bauen oder genehmigen haben nichts in der Luftfahrt zu suchen. Werde kein Mitleid haben, wenn Boeing daran pleite geht."
"With the Boeing 737-Max I was blown away that MCAS is only connected to one of the two angle of attack sensors. People who suggest, plan, build, or approve of such things should never be involved with aviation. I will not feel sorry for Boeing if this will cause their ruin."