I think for me, the hardest thing is to deal with the frustration when things do not work out the way you wanted to and managing your time well, setting your own targets and deadlines.
Nevertheless, even when things do not work out you learn things in the process, so that part is not that bad after all!
I agree with the answer below. Things often go wrong with experiments and studies and it’s often necessary to repeat the same steps over and over. This can be frustrating at times but as was already said, there is almost always a chance to learn something new in the process!
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