Random Issue : Siebel Marketing Activities dont get created after Email Campaign Executes

Hi All,

  We are noticing a random issue, that when ever we execute our email campaigns with proper offer and email treatment then we recieve emails at the designated contacts but the vanilla functionality of activities getting created happens randomly. I.E some times when emails get triggered from the campaign the activities get created next time they dont get..

We want to know are there any specific reasons why this is happening, we have checked the create activity check box every time. We need to know how the Email Marketing - Update Status work flow is creating activities at some times. Notin could be observed from logs..