According to Shiva purana,

"Brahma desired Sarasvati and went to her, asking her to stay with him. She, being his daughter, was furious at this and said, 'Your mouth speaks inauspiciously and so you will always speak in a contrary way.' From that day, Brahma's fifth head always spoke evilly and coarsely. Therefore one day when Siva was wandering about with Parvati and came to see Brahma, Brahma's four heads praised Siva but the fifth made an evil sound. Siva, displeased with the fifth head, cut it off. The skull remained stuck fast to Siva's hand, and though he was capable of burning it up, Siva wandered the earth with it for the sake of all people, until he came to Benares." -- Siva Purana, Jnanasamhita 49:65-80.

What does it mean? Is lord Brahma is incest with her own daughter. Please tell me the actual fact.

According to Shiva purana,

"Brahma desired Sarasvati and went to her, asking her to stay with him. She, being his daughter, was furious at this and said, 'Your mouth speaks inauspiciously and so you will always speak in a contrary way.' From that day, Brahma's fifth head always spoke evilly and coarsely. Therefore one day when Siva was wandering about with Parvati and came to see Brahma, Brahma's four heads praised Siva but the fifth made an evil sound. Siva, displeased with the fifth head, cut it off. The skull remained stuck fast to Siva's hand, and though he was capable of burning it up, Siva wandered the earth with it for the sake of all people, until he came to Benares." -- Siva Purana, Jnanasamhita 49:65-80.

What does it mean? Did lord Brahma want to commit incest with his own daughter? Please tell me the actual fact.