My lab partner and I were collecting some data, and I went to plot it on the computer. I told my lab partner to start the second part of the experiment while I was at it, and due to a fault in the computer it was taking longer than usual. When I finally got back to him, he had collected absolutely no data. He might as well have just been sitting there the whole time.
Containing my anger, I started working with him on the experiment. I took the experimental data with him, and this time, he decided he'd do something responsible and plot the data. I updated my record book, when I wondered what was taking him so long. Turns out he was putting the data into a command line. Not saving it as a file, just putting all the different data points into one command line, taking up about 50 lines of code, and hitting run. If it went wrong, he would simply do it again.
It was a long project we were working on, and we eventually had to come back to it and draw up our data later. I was saying to the staff that we hadn't yet finished the data plot, but then, surprise surprise, he comes in and says he got the plot the night before, and he didn't tell me a thing! Anyway, that was that, the stuff was handed in, and it turned out the data wasn't plotted correctly. Hence, he had single handedly destroyed the project. What a genius.
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