The chemistry is simple: fat cools and sticks to the pipe wall, wipes snag on it, more fat sticks to the wipes, and the mass grows inwards until it fills the pipe. Once formed it does not dissolve — it has to be physically removed.
Domestic fatbergs form most often in the kitchen waste run and in the first chamber outside a property. Commercial kitchens without a properly sized and serviced grease trap produce them relentlessly.
Prevention is entirely behavioural: scrape plates and pans into the bin, bin the wipes, fit sink strainers, and for commercial premises service the grease trap on schedule and keep the paperwork.