Not making a special effort to move out of home when I started university.

Allowing akrasia to prevent me from applying for a single graduate position at any of the many companies that were hiring Computer Science graduates in my final year of study.

Allowing akrasia to prevent me from joining any clubs or associations at university.

Not getting a minimum-wage job for work experience when I was still young enough that the minimum pay for me was lower, giving me a competitive advantage.

Every time I lie, I regret it a little bit, as I wonder whether the long term trajectory of my life would have been different had I been totally truthful instead of 'polishing' the truth.