The meaning of that final grade on your bachelor, master or PhD certificate.
If you took your tertiary (e.g. university) education in an EU country, you are highly likely to have been graded using the following system (undergraduate & graduate):
Percentage 90 - 100% : Grade 1.3 - 1 : Very good - Outstanding work
Percentage 80 - <90% : Grade 2.3 - 2.0 - 1.7 : Good - Significantly above average
Percentage 65 - <80% : Grade 3.3 - 3.0 - 2.7 : Satisfactory, Average
Percentage 50 - <65% : Grade 4.0 - 3.7 : Sufficient - Barely meets requirements
Percentage 0 - <50% : Grade 5.0 : Not sufficient
The above grades may be held against the following latin categorisation
-summa cum laude: exceptionally good work, with distinction
-magna cum laude: very good work, worthy of special recognition
-cum laude: with praise, good work, above average
-satis bene: satisfactory, average
-rite: sufficient despite its defficiencies
-non probatum, non sufficit, non rite: insufficient
Now having secured the minimum grade in your graduate studies and having satisfied the requirements for admission to postgraduate studies at your chosen university, you can be admitted for PhD studies (structured PhD programme or individual doctoral research & study). Your doctoral studies & research will be subjected to three assessment stages:
1. PhD Dissertation will be assessed and graded by at least two professors with the possible grades being:
-opus eximium, exceptionally good work
-opus valde laudabile, very good work
-opus laudabile, good work
-opus idoneum, satisfactory work
*there is no grade for unsatisfactory work
2. Either a:
Rigorosum: Candidate presents his/her analysis of a pre-selected topic to a panel of examining professors and thereafter answers questions from the panel, or
Disputation: Candidate conducts a public lecture on a topic of interest followed by a Q & A session with professors, university community and public participating.
The examining professors grade the rigorosum or disputation whereby the possible grades are:
-summa cum laude: exceptionally good
-magna cum laude: very good
-cum laude: good
-rite: satisfactory
*there is no grade for unsatisfactory work
Both the grade obtained on the PhD dissertation and that obtained at rigorosum/disputation find their ways into the candidate's overall grade.
3. Defence
Supervisor and professors as well as other members of the University Community will participate.
The candidate will make a presentation of his/her PhD dissertation and its contribution to knowledge followed by a Q & A session besides clarifying unclear aspects.
Based on the defence of the dissertation, examining professors confirm the final grade(s) awarded to the PhD candidate. If the professors who assessed the dissertation raised points for improvement and the candidate proves that he or she worked on those points and has improved the dissertation in preparation for publication, his or her chances of strong grades are high.
Example of a final grading: A 'magna cum laude' in Rigorosum and an 'opus valde laudabile' in the dissertation.
Whereas it is rare to completely fail at this stage (coz. weak candidates get weeded out in earlier stages), one's overall achievement maybe downgraded in case significant weaknesses become visible at this final stage.
Once the aforementioned stages are successfully completed, the candidate needs to publish his/her work before starting to use the 'Dr' title.
Now, I know that we are living in confusing times but I lack sufficient information to speak about how the prophets in churches obtain authority to call themselves doctors.
Note: This is general information. Variations may exist for individual institutions and/or countries. There are also honorary degrees being awarded by institutions based on their own criteria.
I wish you all the best. For those keen on exploring more about: postdoctoral positions, junior professorship, associate professorship, full professorship