Having a selection of slightly different tones at your fingertips can be really helpful when playing jazz. If you’re playing a guitar with two pickups, individual volume and tone knobs for each pickup can help you establish the perfect rhythm and lead tones. For example, dial back the volume a little on the neck for rhythm sounds, then switch to your bridge pickup at full volume, with a little of the tone rolled off for solos - there are so many options without having to look at a single pedal.