My glasses are always dirty, I use my tshirt to clean them every day or so. They are full of little scratches, but if I don't focus on them, I don't notice them

My glasses are always dirty, I use my tshirt to clean them every day or so. They are full of little scratches, but if I don't focus on them, I don't notice them. My old pair (which I keep in case my current pair breaks unexpectedly) are even worse, with big visible scratches. They (the old pair) lasted at least 4 or 5 years, and the current ones are at least 3 years old, but I don't really remember.