Its about wasting the time, but strata czasu its waste the time, and szkoda its that you are sad about wasting the time. There are synonims

We use both of them to say about wasting time :)

Szkoda - damage, detriment Strata - loss Szkoda czasu - Szkoda (czyjegoś) czasu - Damage (of somebody's) time Strata czasu - (to) strata czasu - (it is) a loss of time Meaning is similar, meaning it's time wasted, it's a waste of time, though I think using the first one implies more that it is someone's time that is being wasted, or is "damaged" - as in, not fully utilised - while the second is more passive, not necessarily referring to the subject per se, but being a more general lament - it's a waste of time, in general. Observe & compare: Szkoda całkowita = total loss (when referring to for example a car crash and the car is totalled) Szkodnik = pest, lit. "damager" Bilans strat i zysków = balance of losses & income Stracić zaufanie (do kogoś) = to loose trust (in someone)

thank you

szkoda czasu = strata czasu