Often, when someone is out to prove a point to their peers or themselves, they might end up biting off more than they can chew. They do this without realising they have taken on too much, because they are so focused on making a good impression. This idiom is commonly heard in both social and professional environments.
I made a mistake when I took on the coaching role with the local soccer team. I’ve bitten off way more than I can chew, as I can’t fit my job and my family into the week, too.
I bit off more than I could chew when I volunteered for the extra hours. I hope it stands to me for any future promotions.