I see quite a few HN commenters asking, "why isn't this automated?" Well, it is! In 1994 one of the pioneers of vector fonts, Peter Karow, worked at Adobe on "optical kerning", which inferred kerning pairs for a font automatically. Adobe's algorithm models the whitespace between two letters as a viscous fluid which resists flowing into tight areas. They compared it to hand-kerning and found that neither approach was perfect, but that there were 120% more deficiencies when kerning by hand and 30% redundancy in the kerning pairs. So computers, can and do kern better than humans. However, there are still many poorly kerned fonts around, even digital versions of classics such as Times don't ship with particularly good kerning pairs, so designers often find themselves having to tweak kerns.