I had a contractor do some tile work on my house and I noticed the grout is sort of spongy and soft. It doesn't feel like the grout around the rest of my tiles. Anyone know what this could be? Is there such a thing as soft grout?
If it's at a joint between two planes (e.g. wall and floor or inside corner), then it can be colored or even sanded caulk. Using grout in a corner results in cracking as the structure moves, so caulk is recommended for those joints.
Otherwise, you may have an acrylic grout additive to increase flexibility and reduce cracking.