The honest truth is simply because it works no other way. Here are the reasons why:
1) God is always on your side (Joshua 1:5; Hebrews 13:5), it takes recognizing Him to make the difference
2) Your skills, talents and gifts are linked to your calling.
3) You’ve been given your gifts to give courage and hope to someone else
4) Your excellence in your domain enables you to be rewarded and promoted
5) Gratitude and saying Yes count for something
6) You are blessed because you are a blessing
7) Working hard to work smart helps you recognize opportunities
8) Uncommon favor comes with solving uncommon problems
9) You do it well because you love it
Whatever may be your task, work at it heartily (from the soul), as [something done] for the Lord and not for men,
24 Knowing [with all certainty] that it is from the Lord [and not from men] that you will receive the inheritance which is your [real] reward. [The One Whom] you are actually serving [is] the Lord Christ (the Messiah)
And such as violate the covenant he shall pervert and seduce with flatteries, but the people who know their God shall prove themselves strong and shall stand firm and do exploits [for God].
2 Thessalonians 3:13
And as for you, brethren, do not become weary or lose heart in doing right [but continue in well-doing without weakening]
And let us not lose heart and grow weary and faint in acting nobly and doing right, for in due time and at the appointed season we shall reap, if we do not loosen and relax our courage and faint
1 Corinthians 10:31
So then, whether you eat or drink, or whatever you may do, do all for the honor and glory of God
In everything I have pointed out to you [by example] that, by working diligently in this manner, we ought to assist the weak, being mindful of the words of the Lord Jesus, how He Himself said, It is more blessed (makes one happier and more to be envied) to give than to receive
He becomes poor who works with a slack and idle hand, but the hand of the diligent makes rich.