Gen 2:24 Therefore shall a man leave his father and his mother, and shall cleave unto his wife: and they shall be one flesh.
Many people prefer to be married, they can do God's ministry more effectively as married.
One reason is given in 1Cor. 7:2, 35-36:
"to avoid fornication, let every man have his own wife, and let every woman have her own husband. . . . that ye may attend upon the Lord without distraction.
But if any man think that he behaves himself uncomely toward his virgin, if she pass the flower of her age, and need so require, let him do what he will, he sinneth not: let them marry.