What makes a DJ good, according to your opinion?

I think a good dj is up to date with current music and songs that the crowd will know. This depends on the environment of the venue... Maybe the people on the dance floor want to hear hip hop and rap or top 40 music... If the crowd is older the music might be different. A good dj knows how to read the crowd as well. Maybe people want more high energy music, or maybe they want to slow it down. A good dj also knows how to keep everyone on the dance floor, and by the time the party ends or the club closes everyone will wonder how the time flew by so quickly!!

Someone who can use songs that are very different and make them flow so that people get a huge variety of sounds and styles into one listening experience.

probably creativity also because we are talking about music and amusememnt so i think the most original thins can be much more considered especially for a dj i suppose..