One reason is because of the Devil. 1 John 5:19 says "We know that we originate with God, but the whole world is lying in the power of the wicked one." Satan has power over the world, and he influences humans to be as selfish, greedy, and shortsighted as he is. John’s words about the world are manifestly true. The wars, crime, cruelty, oppression, dishonesty, and immorality that are so rampant today give evidence of Satan’s, not God’s, influence. (John 12:31; 2 Corinthians 4:4; Ephesians 6:12)
But, also it is the attitudes that are manifest in people today. According to 2 Timothy 3:1-5 - "But know this, that in the last days critical times hard to deal with will be here. 2 For men will be lovers of themselves, lovers of money, boastful, haughty, blasphemers, disobedient to parents, unthankful, disloyal, 3 having no natural affection, not open to any agreement, slanderers, without self-control, fierce, without love of goodness, 4 betrayers, headstrong, puffed up with pride, lovers of pleasures rather than lovers of God, 5 having an appearance of godliness but proving false to its power; and from these turn away."
God's Kingdom under the head of Christ Jesus, will soon do away with the Devil's influence as well as all wickedness. (1 John 3:8)
Find out more.
jw.org/Good News From God