#1. Highest Cost

#2. No need to hire experienced staff, as this gives them a framework to quickly build lifecycle experience by making mistakes

#3. Never complete the project, because, agile, you know

#4. Easy to manage because things are changing every day

#5. Hide cost of switching to new technologies with ease.

"agility" is a great idea. software without a careful elicitation of requirements and an actual design before construction is a waste. (web app people relax. this does not mean you)