Internally geared hubs allow the rider to easily go from a harder gear used at higher speeds to an easier one as the rider encounters a stop sign or light without having to plan ahead. A poorly planned, large shift of gears at a stop on conventional derailleur eBike could result in major damage to the drivetrain - so internal gears are ideal for riders less accustom to anticipating gear changes when coming to a stop.
Lower maintenance (aka long service interval) is another sought after feature of the internally geared hub - less exposure to the elements mean less wear - but when service is needed it is more technically challenging than a derailleur bike. Internally geared hubs allow for the use of enclosed chain guard to both protect the chain from dirt that will wear it out faster, and your trousers from getting dirty.
Of course there is no free lunch - internal gears are a premium upgrade and they are heavier. Rear wheel removal to fix a flat is much more of a challenge with internal gears, even more so with an enclosed chain guard. The chain has to be re-tensioned which can be tricky if you have never done it before. Some of the internally geared hubs have a more limited gear ratio - the ratio of the highest (for speed) to the lowest gear (for climbing). Derailleur gears are typically 300-400% with a single chainring, 4-500% with two chainrings. Nexus 8-speed has 309% which can be limiting if you want to have speed and low gears for climbing. Rolhoff 14 speed hub has a gear ration of 500%. Nuvinci 380% range and the Nexus 11-speed 411%. Overall though, if you are looking for low maintenance or clean lines, internal gears are a choice you will appreciated for years to come.