Why is this an issue?

It is needlessly complex to invert the result of a boolean comparison. The opposite comparison should be made instead.

Noncompliant code example

if (!(a == 2)) { ...}  // Noncompliant
val b = !(i < 10)  // Noncompliant

Compliant solution

if (a != 2) { ...}
val b = (i >= 10)