...as already pointed out.
I know I don't really need too much evidence, but here we have some numbers about failure rate on IT projects. They can be handy someday ;-)
It summarizes different studies, including some embarrassing bad numbers:
- 51 % (of the surveyed people) viewed their ERP implementation as unsuccessful* 31.1% of projects will be canceled before they ever get completed. Further results indicate 52.7% of projects will cost over 189% of their original estimates
- only 16.2% for software projects that are completed on-time and on-budget
Yeah, I've not given the details about how these numbers were obtained. See the linked article, if you are intrigued.