While none of the following is career altering, it's accurate ;)
Some lighthearted realizations from my holidays:
My family traveled to Brazil over the holidays. In December, I attempted to learn the basics of Portuguese. Interestingly, my 10-year-old picked up more Portuguese during our flight from SF to Sao Paulo than I did in one month! I "realized" the difficulty of picking up a new language at my age.
I took on a 7-day digital detox during the holidays, disconnecting from work and personal emails, as well as other digital distractions. Contrary to the myth that one adapts quickly, I "realized" each day is equally challenging. The seventh day was as daunting as the first. I slipped more than once.
I read few books over the holidays, all on healthy living and longevity, each from different world cultures. The essence of each book is simple, four to five control variables, and they are remarkably similar. No silver bullets. As with #2 above, I "realized" the most challenging aspect here is discipline - especially resisting the mango souffle for me ;)