Lead generation agencies - a consultant's friend or foe?

Thousands, and thousands, and thousands of pounds. That's what Phil lost to a lead generation agency this year.

Is this common in new business lead generation? Or are there some business, like there are consultants, who are grounded and ethical?

So when Phil was approached by Namit from Deliverability Ninja (https://www.deliverabilityninja.com/) - he was invited on the podcast to examine his lead generation approach in much more detail.