Why does frame rate matter for speedruns in games with in-game timers?

Why does frame rate matter for speedruns in games with in-game timers? - Chess Board in Wooden Frame

Watching this video from Karl Jobst, he mentions that the speedruns of several Doom ports must take into account the game's poor frame rate. I know the 007 Goldeneye speedrun on the N64 also involves keeping the frame rate as high as possible. I assume many other games have similar problems.

But I don't understand why frame rate matters in these two games, because they use in-game timers for their timing. I would think if the frame rate dipped, it would slow the timer down just as much. What's going on here?






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Why does frame rate matter for speedruns in games with in-game timers? - Neon Signages Inside a Computer Gaming Shop
Why does frame rate matter for speedruns in games with in-game timers? - From above of aged video game console with cassette and controller with colorful buttons on wooden surface
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Should In Game Timers Be Banned in Speedrunning?




Sources: Stack Exchange - This article follows the attribution requirements of Stack Exchange and is licensed under CC BY-SA 3.0.

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