Some SPSS users argue that it's not really necessary to work from syntax. If something goes wrong or a client doesn't believe your results, you can always recover what you did from your journal file. However, the journal file is no reasonable substitute for syntax. This tutorial explains why.
1. Essential Modifications May be Missing
Manual Modifications under Variable View are Not Recorded in the Journal File and are Strongly Disrecommended
Dictionary information can be edited in the Data Editor window under "Variable View".
For example, one can click the name of a variable and type in a different name. Other essential information such as variable labels and value labels can be edited here as well.
However, such modifications are not recorded in the journal file. In fact, there's usually no way whatsoever to recover these actions.
This may render it hard to convince a client (or even yourself) that there really aren't any mistakes in your final data.
2. Correct and Incorrect Syntax are Mixed Up
When creating a new variable, the result may sometimes differ from what you needed. In this case, you'll probably delete the new variable and try again. However, both the correct as well as the incorrect syntax will be present in the journal file. And there may be some (or many) lines of syntax in between. Because of this mixture, it may be very hard to track down which commands were eventually discarded and which weren't.
3. Syntax from Different Projects gets Mixed Up
If you work on two or more different projects simultaneously, the commands you run will get mixed up in the journal file (which is strictly chronologically ordered). It may take considerable time and effort to separate the relevant from the irrelevant parts.
4. The Journal File May not Get Backed Up
It is generally considered good practice to create backup copies of projects in a highly structured way. Even if questions are raised months (or even years) after a project was delivered, all project files should still be readily available. An SPSS journal file will usually not be part of such archives. In that case, crucial information will be missing if there are no proper syntax files.
5. Indentation is Removed from Python Lines
In Python, indentation contains essential information on the structure of the code. Unfortunately, when syntax is recorded in the journal file, all indentation gets stripped out. In order for the code to work properly, the correct indentation levels must be manually reinserted. However, it may not be obvious at all what those should be.