Is this grout ok - Tile Advice

[UselessDIYer]

Just moved in to our new house with floor tiles. The grout is meant to be cermento ( but it looks lighter then I remember)
I have tried cleaning them but the grout is patchy and some areas it’s ‘smooth’ and others look ‘Sandy’
I have no idea if this is what it’s meant to look like, but I am disappointed with the overall look. Thanks

 

[Dave]

Looks like it’s been over washed and possibly polymer residue left on the grout surface