I am a master student in mathematics studying in Europe and I am applying to several graduate schools in the USA. They aren't all Top 10 in these dubious rankings, but I am applying to Harvard, Northwestern and Rutgers.
Currently, in the first paragraph of my letter of motivation (=letter of intent, statement of purpose, personal statement, ...) I explain how I overcame a big slump (=phase in which I had not much motivation to learn maths) which I went through after completing my bachelor, so roughly 1 year ago. I mention it because this was an important experience to me, and as a result I feel like a more mature mathematician, and I am now confident that I want to do maths in my life.
However, I read that one should never put negative things about oneself in the letter of motivation, so right now I'm having doubts.
Could people on the admission committee consider having gone through a slump a negative point? Do they only want to hear how awesome I was my entire life?