Signs and wonders are one result of The Baptism of The Holy Spirit (the empowerment and authority to do these). They are used for evangelism to demonstrate The Kingdom of God is there.
People, who seek signs, will not find them unless the demonstration of these serves God's purposes which is either the Salvation of someone or to draw people closer to Him. This is because God wants you to seek Him and not His works.
1 Cor l:22-23 For the Jews require a sign, and the Greeks seek after wisdom: But we preach Christ crucified, unto the Jews a stumbling- block, and unto the Greeks foolishness;
The devil will give you the signs you are seeking so you will follow his brand of Christianity which divides and destroys the Body of Christ and is a form of idolatry as the signs become much more important that the giver. This is the danger in Pentecostalism and why there are so many leaders who fall and churches die! They stop seeking Jesus and glory in the signs.
When you stop seeking God solely and look for His works rather than for Him in them you have a form of idolatry. Satan then has easy access and soon error creeps in, ministers fall and churches die.
Signs are used by God for His purposes and not to fulfill our desires to have them. God does not have to do them and will not if they are sought instead of Him or the benefit of another. The danger is that Satan will give his version of them for his purposes.
This is the danger of signs and wonders that they replace He who gave them (as people become blinded by the miracles and lose sight of the miracle giver, Jesus). Paul Said:
"Te Jews seek a sign and the Greeks seek knowledge but we seek Christ crucified"
It is well to heed his warning!
The world is looking for the supernatural. The Church is generally not providing this as they minister and usually do not demonstrate the Power and Authority of The Kingdom of God. So Satan has been able to present his version of the gifts and win many people away from following Jesus to his new age cult and religions.
When the church demonstrates The Kingdom of God in the Guidance and Power of The Holy Spirit and the Authority of Jesus, only then will people be won for Him and His Kingdom.
If you are not demonstrating The Kingdom of God you had better find out why and what you need to change in your life to be able to do this. Only as you demonstrate The kingdom of God can you minister as Jesus and the Apostles did.
1Co 2:4 And my speech and my preaching was not with enticing words of man's wisdom, but in demonstration of the Spirit and of power:
Only as you hear The Holy Spirit and be led by Him will be in a position to do this and live as a citizen of The Kingdom of God should and live as demonstrate it as you should.