It’s the fault of the person who translated those people’s names into Chinese. This kind of translation is a transliteration, which sounds strange and casual.
For example:
(1) Thaksin
Thai: ? [Pronunciation: Tak1-sin2; Meaning: South]
But I think this name translates well and reflects his character, the kind of person who goes his own way.
(2) Somchai
Thai: ? [Pronunciation: som2-chaay1; Meaning: Very manly]
This is a completely rubbish translation.