Keep in mind that cracked or loose tiles can be damaging to more than just cosmetics. If the surface is damaged, there is a higher risk of injuries (cuts, tripping, etc). If it's come loose entirely or in part you could slip on it, and so on.
The problem with ground coverings is that you generally expect it to be reliable and consistent if it looks like it should be. A single loose, chipped or cracked tile might be worse than an entire floor of them.
Comments
Keep in mind that cracked or loose tiles can be damaging to more than just cosmetics. If the surface is damaged, there is a higher risk of injuries (cuts, tripping, etc). If it's come loose entirely or in part you could slip on it, and so on.
The problem with ground coverings is that you generally expect it to be reliable and consistent if it looks like it should be. A single loose, chipped or cracked tile might be worse than an entire floor of them.