Are there disappointments? Yes, and they affect us. To what end?
LINK
We know that God uses any circumstance, even difficulties, to make a readjustment and get us back on track.
Now therefore, I pray thee, let the power of the Lord be magnified, as thou hast spoken, saying, 18 Jehovah, slow to anger, and abounding in loving-kindness, forgiving iniquity and transgression, but by no means clearing the guilty; visiting the iniquity of the fathers upon the children to the third and fourth generations. 19 Now forgive the iniquity of this people according to the greatness of thy loving-kindness, and as thou hast forgiven this people from Egypt even until now.
20 Then Jehovah said, I have forgiven them according to thy word. 21 But as surely as I live, and my glory fills the whole earth, 22 all those who have seen my glory and my signs which I have done in Egypt and in the wilderness, and have tempted me now ten times, and have not obeyed my voice, 23 shall not see the land which I swore to their fathers; No, none of those who have provoked me will see it. 24 But as for my servant Caleb, because he had a different spirit and was determined to follow me, I will bring him into the land he went to, and his descendants will possess it.
Numbers 14:17-24
There are times when we are very focused on something or someone, so much so that we leave aside or stop observing the Lord. God uses many methods and one of them and one of the most effective that he uses to get our attention again can be disappointment.
Listen to advice, and receive correction,
So that you may be wise in your old age.
Proverbs 19:20
Disappointment comes into play several times, one of them when the Lord spoke to Israel in Numbers chapter 13, when God was leading his people in the direction of the promised land. At that time, God's people were overcome with great fear because of the inhabitants who live in the promised land and so they flatly refused to enter. This resulted in the next generation having to wait 40 years.
They will not see the land of which I swore to their fathers; no, none of those who have angered me will see it.
Numbers 14:23