Shaqeeq Ibn Ibraaheem (rahimahullaah) said: The door of (success and well-being granted by Allaah in this life and the next) has been closed to the creation (i.e. those blinded by the worldly life) in six affairs:
*Pre-occupation with the blessings of (Allaah), whilst being unthankful.
*Desire for knowledge, whilst they abandon (righteous) deeds
*Rushing towards sin, whilst delaying repentance.
*Deceived by their companionship with the righteous people, whilst they abandon following their deeds.
*The worldly life elapses on them, whilst they seek after it.
*The afterlife is approaching them, whilst they turn away from it.
I (Ibnul Qayyim) say: The basis of this is (due to) a lack of fervent desire (i.e. for aakhirah), a lack of fear (of Allaah) and weakness in certainty (i.e. regarding the reward in the afterlife); short-sightedness; humiliation and lowliness of the soul and exchanging that which is better for that which is lower, for if the soul were noble and exalted, it would not have been pleased with something lower.
[Source: Al-Fawaa-id: page: 255. Abridged & slightly paraphrased]