Oftentimes as Christ followers we try to over-spiritualize if an area or a people or neighborhood or a family is receptive to the gospel of Jesus. Thankfully, Jesus and his appointed representatives were especially clear on how we can know if we are investing wisely or wasting our time on a neighborhood or such. The gospel is God's promise to us that if we believe in Jesus as our Savior and confess He is Lord, God will forgive us our sins. A few things should caution against over-thinking the whole thing.
1.) Jesus' command to the disciples. When Jesus sent out the disciples to preach the good news and to help people, he commanded them to stay in a place or home that was receptive. If a place or home was not receptive, they were to wipe the dust off their feet as a sign of that problem and to be free of that place. They then were to move on. (Matthew 10:14; Luke 9:5; Mark 6:10-11 stay vs go; Acts 13:51 wipe dust off)
2.) Jesus' example. When Jesus went to a place, he stayed and lingered if there was work to be done decided by how receptive the people were. If they were not, he moved on. We often think of places like Galilee as sleepy backwaters then, in the 1st century AD. This too is false. There were hundreds of thousands of people living in the area at least, and there were also major Roman cities surrounding the area. Lots of opportunity. (Matthew 8:28-34; Luke 4:24; Mark 6:3-6 especially reveals this)
3.) Paul stayed or left depending on need. Paul went places where people had not heard the gospel before, so as to not build on someone else's work. In our time, that is hard to find, where no one has preached before. There are less and more evangelized places, obviously, and there are some groups without any witness. Though, if you're called to international or regional missions, go for it. But Paul went or tried to go to some places where the gospel had already gone to, such as Rome (hence said letter saying). Bottom line he not only evangelized, Paul also did discipleship work. He tended to work with those who were willing. Places that threatened him, he often went instead to a receptive place. If they were receptive, he stayed.
4.) Temporal judgment. While eternal judgment of course would be a clear sign, the Great Judgment is still future. So while it is generalizing, there are so many examples of it, that we should not ignore it: God judges areas in the here and now for build up sin. We cannot say when a natural disaster or some such thing is judgment. But we cannot (on the flip side) say an occurrence is not a judgment from God's hand. Consider a place like Haggai 2:1-19. Clearly the Lord clarifies some of these events were His judgment to lead His own people back to repentance and faith ("consider"). God meant for this general revelation to convict them. He then added special revelation, the Scripture, so they would change. They heeded it. However, some places do not. So while one shouldn't go around declaring judgments mean something about God's view in every instance or most, we should know deeply as a Christ follower sometimes judgment comes to a place or people in sin.
5.) David with Saul and Jonathan even eventually.
6.) Lot with the Valley. The community there rejected righteous living and tried to punish it with lewd expressions. They mocked and scoffed at righteous correction via Lot. Their time was up.
7.) Solomon in Proverbs 30:33 in the context we are to seek peace.
8.) Hebrews 12:1. Not just sin but any "weight" that hinders. Some weights can prevent your sharing the gospel and running the race as you should. It's not wise to get too specific in our pondering this, but just note it. It could be internal to us or external (area/environs).
9.) Providence. Acts 16:6 the Holy Spirit prevented. // Genesis 31-32 Jacob's move to land of witness. // Then, Genesis 46:1-30. Jacob moves for a time due to drought conditions that no doubt God's hand was in, which served as a witness.
So let's shift gears to applying this now:
Thinking through the above points, you can sense examples of this in real life where the gospel is not received in consideration by a person or by an area clearly (it's meant to be fairly clear). Maybe you have some who consider the gospel, do not give up on them. But there are others in your life who just shut you or others sharing Jesus or urging discipleship down. Those persons or areas never seem to "get it" that Jesus is the way, the truth and the life. Worse yet, maybe they shut the door in your face. How many have been there? What clearer example of point #1 above can there be than these things? Yet we make excuses for that kind of stuff people do. This is not wise, to try to out play God's simple teaching on the subject. The Lord Jesus and the disciples never excused that kind of shutting down or rejecting the gospel. instead they made better use of the time we have on earth. In fact, this is the urging of Paul the Apostle, to Christ followers in Ephesians 5:16 that we make the best use of time because the days are (not might be) evil. There are time wasters and people who inadvertently are bogging down sharing the gospel with others or helping others grow. So just be aware of all of this and think how it applies in your personal ministry to others as a Christian.