Japanese requires a giant Mt. Fuji amount of time. You calculate simply that the more time you have, the more time you can study, and the quicker you climb that mountain. So when you are a full-time student (unrelated to Japanese), or full-time worker, which is 95% of you, you start to internally complain:
I wish I had the time to study more – I would be fluent so much faster.
You start to wildly imagine quitting your job, or graduating, and devoting your time to a full-time Japanese study schedule. Maybe move to Japan and go to a Japanese language school for a year. Or just devote all your time to self-studying. Without having life getting in your way, your Japanese will be transformed.
Good news for you. This isn’t necessary, and may even be counter-productive. Everyone’s experienced at some point the simple concept of:
I get more done when I’m busy.
It feels magical, but it’s not. When you have limited time, you are forced to schedule, to plan, and be strict with that time. If you only have an hour in the morning and night to study, you are going to make sure that you have no distractions and will absolutely use those 2 hours to their fullest.
When you are busy, everything must be done more efficiently, Japanese or not. If your work isn’t finished, you won’t have that Japanese study time. Everything benefits from this efficiency. I was either a full-time student, or a full-time worker during my peak studying. Most fluent people are the same.
The only rare legitimate exception to this are the people going through a rough patch in their life. Finance, family, illness, and other things that make their life extremely busy in a way they can’t control (ex. single parent working 2 jobs). In this type of situation, being busy doesn’t give you more time. You are already maxing out the efficiency of your time, so it’s going to be a challenge to study Japanese.
But this is probably not what you fall into. So you can do better. You can become fluent without being given the blessing of an abundance of time. Still unsure? Assuming you have weekends pretty free, and averagely busy weekdays, do you find yourself studying more Japanese on a weekday or weekend? When you have what feels like all the time in the world, procrastination and distraction take over. When you don’t, Japanese takes over.
Going full-time study?
This is not to say that full-time study is inherently bad. If you are going to a full-time language school in Japan, you will probably advance quickly. If you are going full-time self-studying (example, quitting your job to study Japanese for 4 months), you probably can use this time for a speedy level up. But you don’t have to. You don’t need to.
There are no statistics that say that it is more productive to spend a large amount of money to take off time to study. Rather than think about that, first think about how you can work more under your current time constraints. Master the busy schedule, and you will master Japanese.
Full Japanese study without full-time schedule
Have you been successful without needing to dedicate your full-time schedule to studying Japanese? Did you manage to maximize your time even during the busiest of days?