Vantaggi
Interesting work, though most of the time you get pushed into a box of fundraising/business development if you are young and don't have a phd in something super technical. The most benefit I ever got was that maybe people want to meet up for coffee since I had the branding? Did it ever lead to a proper job offer? No. Once you get branded as a humanitarian it's hard. Did I ever manage to move up to become a UN bureaucrat like P- positions? Not really, but can depend on how aggressive you want to be I guess or how lucky you get.
Svantaggi
Toxic management. Awful HR management. Like any multilaterals i guess. Unless you get lucky. Which doesn't happen often in UNDP. Other agencies have much better organised tracks. UN has been in a major funding crisis for a long time and will continue to be. Not everything that glitters is gold.