Follow up is the killer of many successful marketing campaigns
So many marketing campaigns fail because people send them out, but expect that the first "hit" should result in their telephones ringing off the hook. It's nice to think that this would be the case, but in the real world, that rarely happens.
When executing a marketing campaign, make sure you have enough resources to followup ever single person that has received your campaign. Also ensure that this is done in a timely manner, not months after.
If you are going to invest in a marketing campaign, then you want to realise the full value of the campaign. Try always to have a minimum of three touches with any prospect. If you are doing a direct marketing campaign, ensure that you send the campaign, follow up with an EDM, then a call organising a meeting.