Multi effects pedals provide the guitarist who doesn't have the room or perhaps budget for a custom board with access to a multitude of different effects to be accessed individually or in tandem.
Whether that be modulation effects to be clicked in by different stomp switches, or expression rocker switches capable of pitch-bending, wah and whammy, everything is collected on easily assigned and recalled patches which potentially do away with the need for more than one pedal in your entire collection. Some are clearly intended for home recording but others are available in rugged, tour-worthy chassis.