To include all values you have to check the box that states "Include All Values". This option is available on the screen where you create your value list.
There is a minimum drop size the. The number of items listed changes based on the font and font size. The bigger the font the fewer the items in the list.
All of my values lists have the “Include All Values” radio button marked as selected.
Do you show values from just the primary field or have you selected the "also show values from" option to list values from a secondary field?
Do you specify sorting on the secondary field?
Check for duplicate values in the Title field.
When you show only second field values or sort on the second field values, data from records with duplicate values in the Title field is excluded. You may also have records where there is no matching record in Titles for a given record in "Master Record".
The relationship between Master Record and Titles may also be an issue here.
My choice for use values from first field was the problem.
As you can see from the above snippet I had it set to Master Records.
When I changed the choice to Titles the issue went away and all the items in the value list displayed as expected.
FWIW: That incorrect referencing turned out to be the cause of my database crashing whenever I tried to make changes to the tables. I had even re-installed FMP thinking it was possibly corrupted.