The word Adept brings a lot to mind, so much so that I believe it necessary to clarify some things regarding Adepts in the Golden Dawn system.
Firstly, using the word Adept on its own is a bit of a misnomer, for the Golden Dawn classified Adepts based on just how much they knew and could do (within the context of the system). Those who are advanced to 5=6 were Adepti Minores, which shows that they are Lesser Adepts, in much the same way there is a Lesser Ritual of the Pentagram before the Supreme Ritual is taught.
Only at 6=5 is an initiate an Adeptus Major and only at 7=4 is he or she an Adeptus Exemptus.
Yet within these lofty grades are a set of sub-grades, which specify even further the level of the initiate. For example, in 5=6 we have the Neophyte Adeptus Minor, Zelator Adeptus Minor, Theoricus Adeptus Minor, Practicus Adeptus Minor, Philosophus Adeptus Minor, and finally Adept Adeptus Minor. All of that is before 6=5 is even approached.
Of course, historically the Order collapsed before anything beyond Theoricus Adeptus Minor was created, and both the Stella Matutina and later Alpha et Omega abolished the sub-grades and moved material to higher grades. Many modern orders, however, have restored these sub-grades and implemented relevant teachings.
The beauty of the sub-grades, beyond the fact that they are useful divisions of content, is that they are somewhat humbling. The new Adept not only has to remind him or herself that he or she is just an Adeptus Minor, but a Neophyte Adeptus Minor. He or she is "newly planted" once more and very much a beginner in the new material he or she will be learning and practising.
The process extends further into 6=5 and 7=4, where the sub-grades may also be employed. Some groups keep these as single grades, but there appears to be some evidence to suggest the Alpha et Omega, at least, adopted sub-grades at these levels in its early years, suggesting this was the intended structure for the Golden Dawn as well.
Thus, when the Adept, who recognises that he or she is a Lesser Adept, has gone through the process of Neophyte to Philosophus within this first Adept grade, and now dons the title of Adept Adeptus Minor, he or she is now faced with being "newly planted" all over again as a Neophyte Adeptus Major. Further still, when the sub-grades of that grade are undergone, it begins again with Neophyte Adeptus Exemptus.
This might seem like an overly complex way of doing things, but it does show that Adepthood is just the beginning, in much the same way a black belt in a martial art is. The Outer Order is preparatory, while entry into the 5=6 does not mark achievement, per se, but rather the start of the quest in earnest towards that achievement.
Thus, when we speak of Adepts in the Golden Dawn system, we might be discussing very different things, or people at very different levels. This does not even take into consideration the vast differences between people, their experiences, their skills, and how dedicated or not they are to the Great Work. All of these factors make for very different Adepts at very different stages of their magical maturity, and even the grade structure itself, evocative as it is, is merely symbolic of spiritual progress that cannot be so easily defined.