There are only five Categories of Gross Auditing Errors (GAE's):

1. Auditor can't read or use a Meter.
2 Auditor doesn't know or can't apply technical instructions and data.
3. Auditor can't keep the pc in-session.
4. Auditor can't complete an auditing cycle.
5. Auditor can't complete a repetitive process to EP.

These are only categories and all auditor errors fall under one of these.

There are six things, that can prevent a pc from making it:

1. Pc is a suppressive person.
2. If the pc's case 'roller coasters' - meaning pc gets case gains, looses them; comes in for more auditing with gains, but looses them as well - The pc is a Potential Trouble Source (PTS). This condition is caused by a suppressive person close to the pc. Finding the right SP and handle the pc on it and clean it up is the only thing that will handle. There is no other reason for loosing gains obtained in auditing.
3. Pc is being audited over an ARC break. You never audit an ARC broken pc, even for a minute. You must find the By-passed Charge with Meter Assessment and indicate the By-passed Charge at once. To audit a pc over an ARC break will worsen his case.
4. A present time problem of long duration prevents change and gains.
5. The only reasons a pc is critical are Withholds or misunderstood words. You must pull Withholds. It's something the pc has done - something where pc was at cause.
6. If the pc is continuously committing Overts he won't get case gains. This is a special category of # 1, suppressive person.

To get the technology in and correctly applied, you only need to look for the 5 categories in the auditor and the 6 categories concerning pc's. There are no other reasons.

The above points were written up by Ron Hubbard in September 1965. They hold true even today.

But let us look at them for a minute in hindsight:

1. Auditor can't read or use a Meter.
This is covered and remedied by doing the basic materials on metering and Meter drills in this manual.

2. Auditor doesn't know and can't apply technical instructions and data.
The key is to use the study technology, when studying the materials. Another important point is to thoroughly drill all procedures on a doll, before going in session and delivering them to a pc.

3. Auditor can't keep the pc in-session
A key definition in the technology is 'in-session': Pc interested in his own case and willing to talk to the auditor. Especially in the TRs section there are a lot of data about this and how to accomplish it.

4. Auditor can't complete an auditing cycle.
This is also best covered in the TRs section. Especially data about TR-2, ending a cycle with an acknowledgment, TR-3 Getting your auditing question answered and TR-4, originations. Also data on Q and A (in 'Communication and Auditing') applies here.

5. Auditor can't complete a repetitive process to EP.
This is covered in TRs, especially TR-3; but also data on 'F/N's and EP' are important here.

All the auditor points are thus covered in this manual and in 'Study Basics' that you should study before Level 0. In the case of weaknesses in one or more areas become evident, it is important to restudy the materials with special attention to misunderstood words. They have to be cleared thoroughly and the materials restudied and drilled again.

This manual does not covers the study materials and the study technology in great depth, but we do have a section on Study Basics.

Let us now take a look at the six points, that applies to pc's:

1. Pc is a suppressive person
Ron Hubbard defines an 'SP' as follows:

Suppressive Person, 1. He's solving a present time problem which hasn't in actual fact existed for the last many trillion of years in most cases.  Yet he is acting upon it in present time to solve that problem. The guy's totally stuck in a past incident and thinks it is present time; that is the whole anatomy of psychosis. 2.He covertly tries to destroy or speak bad about any effort to help anybody. He is violently opposed to anything intended to make human beings more powerful or intelligent. A suppressive automatically and immediately will oppose any betterment activity, calling it evil or bad. 3. the person is in a mad, desperate situation of some past incident and is "handling it" by committing Overt acts today. 

So it is somebody who overtly or covertly is working against the auditor and the auditing. The handling of such a person is outside the scope of Level Zero. They are considered to make up only about 0.5% of the general population. They should not be accepted for auditing. (Se also CT-4 Pro for data on this).

2. the pc's case 'roller coasters'.
A PTS is under the bad influence of an SP. This can usually be handled with Ethics counseling (outside auditing). A Class 0 auditor should not as the first thing try to handle a difficult case like that as the technology for handling it is not included in the level. PTS people is estimated to comprise about 19.5% of the general population. There is workable technology for handling this condition in CT. It consists of Ethics counseling as mentioned above, followed by an auditing action, called the PTS Rundown. (Se also CT-4 Pro for data on this).

3. Pc is being audited over an ARC break.
Handling ARC breaks on Level 0 are covered under 'Flying rudiments' and 'Auditors Rights'. There are two different kinds of ARC breaks as far as the auditor is concerned. There is an 'outside auditing' ARC break to somebody. Then there is a Session ARC break, which is a more serious situation to auditing: pc is unwilling to talk to the auditor. A heavy session ARC break should be cleaned up by a class 3 auditor. If this happens, it usually means prior out TRs on the auditor's part. 'Outside auditing' ARC breaks are simply handled per 'Auditors Rights, Rudiments Going Out.'

4. A present time problem of long duration prevents change and gains.
The PTP handling available at this level is contained in 'Flying Rudiments'. It is possible that a heavy PTP situation is best tackled by Ethics counseling as mentioned above. Somebody, other than the auditor, should simply go over the pc's situation and help him work out a solution in the physical universe, before he continues with his auditing. The complete technology on how to handle problems with auditing exist on CT Level 1.

5. Pc is critical = Withholds or misunderstood words.
The Withhold/ Missed Withhold handling available at this level is contained in 'Flying Rudiments'. Misunderstood words is handled with clearing words with a dictionary. The full technology for Overts and Withholds is contained on CT Level 2. There is also a lot of technology, outside this level, on how to find and clear misunderstood words.

6. Pc is continuously committing Overts.
Leave a difficult pc like that alone at this level of training.

In general, there should be a case supervisor to oversee the auditing and the auditor. He should advice and determine how to handle anything falling under these eleven points. It is outside this manual to give complete instructions on how to handle every and all of these situations. Do your training well and drill it well before taking your pc in session. Start out with pc's that seem to do all right in life, but want improvement and the auditor will get some wins and get onto the next levels of training where he step by step will get all the technology of CT.

See also section "Who can you help?" on CT-4 Pro.