Most earthquake faults are sleepy things that just lie there until an earthquake happens in one sudden jolt. But a few interesting faults exhibit creep: they creak along quietly, smoothly, very slowly, as if they were hoping you won't notice. But geologists notice. Creeping faults are somewhat mysterious, as I point out in my article on fault creep, but we can say some things about them confidently. Most people wonder if the fact that a fault is creeping means that it's less likely to produce an earthquake. The answer is that while creep must make a difference in the strain that a fault accumulates, it's not a difference that we can notice because earthquakes are so irregular.
Creep-caused cracks Geology Guide photo