Merge lanes are provided for merging into existing traffic. They are intended to give you time to match speed with the traffic, signal, and then blend in. In a perfect merge, you start indicating as you approach the dotted line (where the lanes connect), someone makes space (by moving over if possible, and otherwise by slowing down or speeding up), and you slide over into the lane. All this ideally happens near the beginning of the merge area.
Many drivers, especially those who are a little nervous about driving, do not seem to have been taught that they should merge as soon as possible. Driving instructors should make sure that their students learn about the 'courtesy point', the point at which the merge lane joins the traffic lane. That is where the dotted line starts, and it is where your car becomes part of the traffic flow. To drive courteously, you should try not to pass anyone already on the highway. Use the approach to try to match the speed of traffic. Then, as you approach the courtesy point, signal your desire to come over and do so as soon as you have space.
One of the worst things you can do is race ahead, get to the end of the merge lane where you have no more space, stop, and try to get into the moving lane. All that does is frustrate the other drivers. It does not help you at all, and it is guaranteed to interfere with traffic flow. Every driver who does it slows down the traffic flow for everyone else.
Even worse, I have seen drivers who are in the normal (moving) lanes go over into the merge lane and use it to pass other cars. Again, that significantly slows down traffic flow and affects all of us. Since the driver has to slow down to merge back in again, everyone he passes loses more time than he gains. Before you jump into the merge lane to pass other people, think for a minute. What if you were lined up for a bus, or a movie? Would you expect to be able to walk around the line and jump in at the beginning, slowing down everyone else just so that you could get in first? You would expect people to get angry, wouldn't you?
When you are merging, just remember the 'courtesy point', where the dotted line starts. If you signal your desire to come over at that point, you will find that most drivers are perfectly willing to let you in. Once you have passed the courtesy point, remember that you are now part of the traffic flow. Try not to pass anybody already in the traffic; that only makes people angry. Match speed, signal, and come over as soon as somebody gives you space.