With the not following through thing. Just off-hand there's a few reasons for this:
1. We usually try to come to a consensus between the moderators before infracting. If the offence is particularly egregious, or one of us (me) is feeling particularly grumpy, we instantly infract, but otherwise we try to agree on an infraction. Clearly, given the fact that we're spread out across different timezones and this is not a job so we're not always online every day, this can be a problem. (There's also the problem that sometimes we... forget to infract the post we agreed to infract. We're working on this.)
2. The stratified, quantised nature of an infraction sometimes makes it difficult to decide what is an "infractable" post and what is a "warnable" post, which can sometimes lead to indecision and/or inaction. Many of you know my thoughts on this, though, so I won't elaborate.
3. Sometimes we plain don't see the posts we're supposed to be infracting. Or we only get reports which, when removed from their original context, don't make sense as infractable. We do vastly prefer tour threads, which are by their nature fluid, fast-paced and difficult to get an accurate read on after the fact, to be moderated realtime or, barring that, self-moderated. Which is why flamers get on my ****ing nerves so much.
edit: i just saw that there's another thread on this topic. well, that discussion can go in here too~