This question haunts almost all serious Yoga Teachers.
Those who are serious Yoga teachers are also in demand, and many a times also in a need of money. Why so is not discussed here. But, that is the fact. Thus, they automatically spend a lot of time teaching others. Same is the case with those who are trying to benefit others via Yoga in different ways.
Now, obviously one is doing several activities regularly in life. Some of them are biological needs, some are financial needs, some are obligations, and some are duties. An additional activity of most serious Yoga teachers or workers is to do Self Study and Self Practice to improve themselves. When one is performing several activities, one has to give weightage to different activities, also sometimes called prioritisation. Thus, a proportion of time is needed for Self improvement. When such a time is not available, a Yoga practitioner who wants to improve him/her-self gets frustrated. And, that starts putting them on a downward path for two reasons. One due to mental condition resulting from frustration, and the other due to the decrease in knowledge gain or decrease in efficiency due to lack of Study and Practice.
Many times, a person who should actually focus on income focusses on self practice, thus creating a big problem in future. On the other hand, the one whose income problem is solved continues to sacrifice the self practice due to the attachment to teaching. This attachment can be due to ignorance, aspiration for name and fame, and wish to increase income further.
The one who has reached the peak of what they want to do only should think of giving up Self Study or Practice. All others should continue the study in some form. How much self practice one should do depends on the status of the person. But, one should try to maximise the practice considering the other factors, unless of course one has reached the peak of where they want to go. No frustration should be felt in such case.