While reading the paper "Approximate Statistical Tests for Comparing Supervised Classification Learning Algorithms", I am confused at Section 3.3 when the authors claim that the paired t-test is not suitable to use to compare two classifiers $A$ and $B$, because the observed proportion of test examples misclassified $p_A$ and $p_B$ by $A$ and $B$ during trial $i$ are not independent. However, according to my understanding, the paired t-test assumes that the samples are paired, thus dependent.
What I reckon is that the test mentioned in the paper is the unpaired t-test. However, I think there is no motivation to consider unpaired t-test to compare two classifiers.
Thank you in advance!