Re: Agile doesn't cut it.
Nobody develops using pure waterfall so that is a strawman comparison. Perhaps agile has delivered some large complex projects on time and with the required features but I haven't seen it.
I just reviewed an agile project 2 years past due (was 1 year), 4 times over budget, massively reduced functionality (substantially less than the minimum core functionality defined) and still not usable. Clearly from this alone agile projects can go just as horribly wrong as anything else. In this case I think agile contributed to the project not being stopped and actions taken until such a ludicrously late stage.
There are some good things in agile but there is no magic bullet and agile assumed to be a pancea is very dangerous.