I think abbreviations make sense if the abbreviation is better known than the full name, or if it's standard jargon in the problem domain, or it's used so frequ

I think abbreviations make sense if the abbreviation is better known than the full name, or if it's standard jargon in the problem domain, or it's used so frequently in the program that it can be considered a convention. But using abbreviations just to save some typing makes life difficult for newcomers to a project and can be a source of bugs.