Science Songs

Since getting back from holiday I've been having a nightmare getting a certain type of PCR to work. The most recent head scratching moment was to get a round of PCR that worked perfectly. I immediately ran the same PCR with the same reagents and settings but with the DNA samples I wanted to check. Nothing worked - not even the positive controls that had worked 3 hours earlier.
When an experiment can't be repeated with the same conditions there's only a few explanations;
a) there's something you aren't accounting for so it isn't the "same"
b) you are the variable
c) you are switching universes in between experiments
d) there are science goblins messing with your mind

All of these options reminded me of this song

The chorus is

"There are monsters here
And as you scream it makes no sense
It makes no sense
It makes no sense at all "

That pretty much sums up the last 2 weeks of work for me.