These are not grammatically full sentences. It is a kind of abbreviated style that is typically used, for example, for notes or bullet points. In my opinion it is debatable whether it is entirely appropriate for this kind of flowing text.
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These are not grammatically full sentences. It is a kind of abbreviated style that is typically used, for example, for notes or bullet points. In my opinion it is debatable whether it is entirely appropriate for this kind of flowing text. Opinions may vary.
As you say, "completed" and "played" are lacking their subjects. The first and last sentences are lacking both subject and main verb