How are you supposed to read the strip sizes using LibTiff library?

Question

I've seen code like this to get the strip sizes:

// Get strip sizes
    for (tstrip_t i = 0; i < numStrips; ++i) {
        tsize_t stripSize = TIFFStripSize(tiff);
        std::cout << "Strip " << i + 1 << " size: " << stripSize << " bytes" << std::endl;
        
        // Move to the next strip
        TIFFReadEncodedStrip(tiff, i, nullptr, -1);
    }

However to my understanding each strip doesn't have to be the same size and there's also a function used to get an array of the strip sizes. I'm wondering how using TIFFStripSize can be used for the strip size given that the strip sizes may be different?