The tendency in most movies, television series, animes, video games, and just about any medium emphasizing combat for your weapons, armor, and tools to be nigh unbreakable. This is only subverted in perhaps a few RP Gs
(Elder Scrolls and Romancing Saga, for instance) or when a writer needs to make the situation more dangerous for the wielder in question. Feel free to dig a hole to china with the pickaxe you made out of sticks in Terraria - you'll cut right through the 10 miles of iron on the way there. Expect an action hero to probably never have to strip and clean his firearm even if he's been wading through a muddy jungle every day. That level 1 wooden sword the legendary hero wields will likely be fine to use throughout the entire game without splintering or requiring a polish. It might suck ass but feel free to hit as many "Sharp Blade Elementals" as you want, it's cool. The paper shield should withstand meteors and fireball spells for a good year or so too. No, your armor doesn't need to be padded with fire-retardant - it won't burn off or from the sorcerer's "Inferno" spell. Feel free to parry admantium greatswords with the dagger you got at the resale shop.
A few notable subversions exist: Elder scroll games require regular weapon and armor repairs, as does most of the Romancing Saga series. Some games have breakable tools and items or levels of durability, like Diablo, buy many more, if not a majority more, particularly outside of the rpg series, do not.
Most fighting games, even when featuring weapons, will let you play round after round without issues either between or during the rounds, but Vega's claws in the street fighter series actually do break in some games, resulting in weaker attacks with shorter range.