Many have analyzed the defense, including Hans Olsen, and pointed out how the safeties are really poor in their coverage schemes and technique. In particular, they aren't doing very good at passing off receivers from one to another, almost like one is playing a certain scheme while another is playing a different scheme, and nobody knows who they are supposed to cover. This leads to gaps in the coverage and we've been exposed. In addition, tackling has been an issue all year.
In regards to special teams, we know that's been a huge problem. First, that our kickers are missing so many. Second, that our coaches have no confidence to ask the kickers to kick a field goal anymore. Whether THAT is Kalani's call or Lamb's, I don't know, but that doesn't show a lot of confidence in your assistant head coach, when you'd rather try for repeated failed 4th down attempts instead of bringing out the kicking unit that your assistant head coach is directly responsible for.
I don't know how much blame to assign Lamb, as I'm not in practices every day. But certainly, from what we as fans are able to observe, there are clear problems with both of his units.