They have different approaches.
Some countries have a regulator like the CRTC. In Germany, they have kept the power themselves. The CRTC of Germany deals with complaints at the individual level and moves towards systematic fines when it doesn't happen in a systematic manner. Individual cases don't really incentivize bad actors to do better, because they are very small fines, essentially. Sometimes it might have to go towards more monetary penalties.
Some other countries have a system like ours, in that essentially the regulators have outsourced enforcement and compliance with the codes of conduct to a third party organization. In some countries, the competition authorities deal with this, so it's not the telecom regulator directly.