Try as he might, he could never be good enough to please his mom. When good enough never worked, he tried bad enough. What Gru really wanted is love and acceptance. And when those three little girls, the decoys, love him and see him as a potential father, not despicable, he is changed.
The movie made me consider Despicable ME! I too had a mom I could never be good enough for. Luckily I never turned into an evil villain, although I did have my share of despicable-ness (a word I think I just coined). I too was changed by love, the love of God.
With Jesus, I don't have to be good enough. Jesus was good enough for me. The Bible says that while I was still a sinner, he loved me. He loved us. And His goodness fills the voids that my "nice tries" leave.
At the end of the movie, Gru is changed. Not despicable anymore, he is a father loved by his three children. And being a "happily ever after" kids movie, Gru's mom comes around and compliments him on his parenting, the acceptance he never received as a child.
Real life is not a movie. My mom isn't coming around to give me the acceptance I wanted from her. But because of God, I'm not Despicable me. I'm God's pick-able me. Chosen, loved, accepted. And so are you. Not despicable. Pick-able!
"God picked you out as his from the very start."
2 Thessalonians 2:13, The Message