Motivation is very important when learning a language, or indeed anything else. Without motivation it’s difficult to continue studying for very long.
An enthusiastic teacher or tutor can really help, as can learning materials at the right level, i.e. one that stretches you, but not much. Setting yourself targets and goals, and rewarding yourself when you achieve them can also help. Another good way to motivate yourself is to spend time studying the language in a country or region where it’s spoken.
Way back in 1988 when I first tried to teach myself languages, I found it very difficult to continue studying for more than a few weeks. My lack of motivation was the main reason. Since about 1998 though, I’ve been studying various languages more or less continuously. Motivation seems to come more easily to me these days.
How do you motivate yourself to study?