Leads themselves are not a success if they are of poor quality. I had an experience when there seemed to be a flow, but there was no use, until I came across professional b2b lead generation services and immediately felt the difference. These guys do not just collect a database for the sake of numbers, but really filter who fits your profile. The quality of leads is noticeably higher, people respond, dialogues are ongoing, and do not just hang in the air. Everything is transparent: reports, status for each contact, you can control at what stage what is happening and there are no problems with communication at all.