"I will pour abundant blessings on all their undertakings."
What guarantees success or failure in your life's projects, dreams and goals?
Perhaps that's just it. If our goals and efforts are all ours and ours alone; if they are not asked of God, inspired by God and lead by God, what kind of "success" can that be?
Our only true "success" is the salvation of our souls. "What profit is there to gain the whole world and lose your soul in the process?" Jesus asked in the Gospel.
So we go to the Sacred Heart of Jesus, a Heart that wanted only two things : that the Father's will be done; and that souls be saved - both things for the glory of the Father. In His Sacred Heart, we learn to love God above all things, and our neighbor as ourselves. He teaches us obedience, docility, meekness, humility, perseverance in trial, courage in difficulties. When we feel like abandoning our mission in life which God has given us, we find power to carry on in the Heart that went to the cross.
Our dream, our goal in life must be God's will for us. That is the only enterprise that can be successful. If you are married, to be the best spouse. A priest? Student? Accountant? Widow? To live your station in life doing the best in it, with God's glory and the salvation of souls as your highest interest.
Therefore, if you ask God for "success" in this or that, and it doesn't come; perhaps God is teaching you : what you ask for will harm your soul. You do not see how this can be, but one day you will see.
When we walk in His ways and follow His law, God provides for us - not everything we want - but everything we need for our salvation. Sometimes this means the cross, but also the graces needed to carry it. But life is not all crosses and difficulties. Does not God lavish us with spiritual and material graces, even though we don't ask for them and have little or no control over them? The sun, the rain, fair weather, our intelligence, our talents? Will God not then care for, spiritually and materially, those who, through devotion to the Sacred Heart, seek to do His will and follow His ways? And, as the promise says, not just blessings, but abundant blessings.