Really odd if we don't sign anyone. Without another CB we will almost certainly not win the title (unless we get really lucky with Fab and, in particular, Matip). Whereas with another CB, I would make us favourites (maybe joint favourites with City).
I know that money is tight for everybody, but that means players should be available cheaper, as some clubs need to sell, and others can't afford to buy (or at least to spend as much when they do).
We need to look at the fact that we will probably need to buy a CB in the summer anyway (cos of Matip's injury issues, Gomez likewise has got a pretty big injury history, and now that c**t Pickford has even left Virgil with a question mark about how resilient he will be after he comes back. Painful to even think about that, I know, but it has to be done. Hopefully he will be back as strong and durable as before, but we don't know that, and anyway the other 2 are definitely already injury prone.)
Basically if Jürgen doesn't think Phillips or Williams are going to cut it long term, we will need somebody else as cover at the very least anyway. So we should get them in now when prices are lower (even if it means taking on a bit more debt or whatever). We're only postponing the expense by delaying, and the price of the postponement is likely to be this season's title chances.