Just as God chooses who He wants to be a teacher in the church, He also chooses who He wants to speak in tongues. He doesn't give everyone the same gift. There are many gifts for the many functions involved in building up the body of Christ.
There are different kinds of gifts, but the same Spirit. There are different kinds of service, but the same Lord. There are different kinds of working, but the same God works all of them in all men. Now to each one the manifestation of the Spirit is given for the common good. To one there is given through the Spirit the message of wisdom, to another the message of knowledge by means of the same Spirit, to another faith by the same Spirit, to another gifts of healing by that one Spirit, to another miraculous powers, to another prophecy, to another distinguishing between spirits, to another speaking in different kinds of tongues, and to still another the interpretation of tongues. All these are the work of one and the same Spirit, and he gives them to each one, just as he determines. (1 Corinthians 12:4-11)
Ironically, we Christians have made speaking in tongues a big issue, yet it is last in the list of the gifts of the Spirit.
Now you are the body of Christ, and each one of you is a part of it. And in the church God has appointed first of all apostles, second prophets, third teachers, then workers of miracles, also those having gifts of healing, those able to help others, those with gifts of administration, and those speaking in different kinds of tongues. Are all apostles? Are all prophets? Are all teachers? Do all work miracles? Do all have gifts of healing? Do all speak in tongues? Do all interpret? But eagerly desire the greater gifts. (1 Corinthians 12:27-30)
There are much more important gifts than speaking in tongues, such as administration and helping others. But everyone should desire the greatest gift of the Spirit: To communicate God's love --His good news-- to others.
And now I will show you the most excellent way. If I speak in the tongues of men and of angels, but have not love, I am only a resounding gong or a clanging cymbal. If I have the gift of prophecy and can fathom all mysteries and all knowledge, and if I have a faith that can move mountains, but have not love, I am nothing. If I give all I possess to the poor and surrender my body to the flames, but have not love, I gain nothing. (1 Corinthians 12:31-13:3)