We can find ourselves in several types of situations.
1. If we are not awakened spiritually (the case of most practitioners on an authentic spiritual path) then we really need a master spiritually to guide us, to explain and appropriate the methods of transformation to our concrete situation and, above all, to help us overcome our own obstacles.
These obstacles tend to make us find motivations and justifications so as not to transcend them and to choose from the Path only what suits us.
When we do not benefit from a minimal spiritual awakening we find it difficult to maintain constancy and intensity in our practice and we need help with it and guidance, especially in key moments or points.
So it takes the master or the spritual guide.
2. If we have a minimum spiritual awakening, at least at the level of the living soul (jivatma) then we have an authentic inner guide and the need for guidance decreases to no longer need it except rarely and only in relation to certain essential aspects.
The problem is that many people have the arrogance to believe that they already have this minimal awakening and that they manifest it constantly enough that they do not need the master.
This is a danger generated by the ego that lowers the level of awakening (which is not always constant) and can give the spiritual seeker the feeling that he can guide himself and, as in the previous case, that he can choose from the spiritual path that suits him.
But a deep and constant awakening of the living soul jivatma can indeed provide a wonderful guidance (if it is real).
At this level we still need to carry out sustained spritual practice, but we do it easily and with wonderful and obvious effects.
3. If the inner awakening is so profound that we feel integrated or whole in the Supreme Self (Atman) then we really do not need the Spiritual Master. We don't necessarily need a spiritual practice, but if we think it is necessary, we do it easily and with exceptional energy efficiency.
Attention! however advanced our spiritual realization may be, falling into outerity and ego is possible, and here is also the one that says:
"The higher you fall, the harder you hit yourself."
So even in this wonderful state of spiritual development in which we feel integrated or whole in the Supreme Self (atman) it would still be better to have a master who would help us not to derail and cause a fall, because it is known that when we wake up spiritually we feel, but when we fall, unfortunately, we do not feel it.
If we benefit from awakening at a significant level of Kundalini energy or if our path has a tantric hue or is even authentic tantra, it is very important and essential to guide a competent spiritual master.
Most spiritual failures or "rebutts" occur in these two situations.
An authentic spiritual master does not lead his disciples at his feet but "at the feet" of God or the Infinity of their True Potential.