Root locus gain k=inf

Hello everyone

so I was coding a questions to get comfortable with Matlab and everything seems alraight .However one of the question gives me the root loucs gain K Inf which I honslty don't know what it means.here is the code I did

s = tf('s');

#case-2

kp=3

ki=2*kp

Gcs=kp+ki/s

delta=2.5;

Gs=[(6*s-10*delta)/(s^2+3*delta*s+100*delta)]

CLTF2=feedback(Gcs*Gs,1)

rlocus(Gs)

Gm=margin(Gs)