Everyone has weakness. It just shows more in some rather than others. Even the strongest, smartest and most successful have weakness.
Christians have weaknesses. Some wrongdoings are much more tempting than others.

As you try to do right in life, remember the enemy of God, the devil, knows your sin weaknesses and will work hard to destroy any honor you have given Christ through your life. But Jesus promises overcoming strength to help you.
LET every one consider what his weak point is; in that is his trial.
His trial is not in those things which are easy to him,
but in that one thing,
in those several things,
whatever they are,
in which to do his duty is against his nature.
Never think yourself safe because you do your duty in ninety-nine points;
it is the hundredth which is to be the ground of your self-denial.
It is with reference to this you must watch and pray;
pray continually for God’s grace to help you,
and watch with fear and trembling lest you fall.
Oh that you may (as it were) sweep the house diligently to discover what you lack of the full measure of obedience!
for, be quite sure, that this apparently small defect will influence your whole spirit and judgment in all things.
JOHN HENRY NEWMAN
Taken from Back to the Bible, Joy And Strength devotion, Mary Wilder Tileston.