My wife got this from her PhD mentor, who reportedly said something to the effect of "...and evangelicals say they have no liturgy!" See for yourself.
"Sunday Morning" Movie Trailer
Did you watch it? No? Go back up and do so now. Go ahead. I'll wait.
Done now? Good.
If you laughed, you did so because you know that what this video is talking about is true. These patterns exist in many "contemporary" worship gatherings today. These "patterns" are what a liturgy is. It's "how" these churches worship, and if one or more of these "patterns" are changed without warning, people notice. That's not to say that they'll always complain. Not all change is bad. But they generally will notice that the pattern--that is, their liturgy--is different.
Many Christians--not just those who worship in "contemporary" settings, but certainly including such worshipers--often argue that they don't have a liturgy. When they say this, they probably mean that they're not bound to a formalized set of worship instructions such as that found in, say, the Episcopal Book of Common Prayer. But they do have a liturgy. All churches do. It doesn't have to be formalized by being written down. It just happens. People create patterns that reflect who they are as followers of God.
And there's nothing wrong with that. It's actually a good thing. But I also believe that Christians would benefit from becoming aware of just what their own patterns of worship--their liturgical practices--actually are. Because if they don't do it consciously, it will often happen only when someone stands up to complain "but we've never done it that way before!"