Half of Europe has widely used national systems for instant payments, the other half does not. The idea behind Wero is to unify this to one single system, available across whole Europe. For reference, I use these systems for like 80% of my online payments.
Of course nobody's using Wero now because the whole thing isn't really online yet, just a pilot program on a few websites with a few banks.
WERO is an application/UI layer on top of SCT INST payment scheme, which adds some additional features like "send to email" etc. as well as other pay-specific features in the future (pay-per-request, which is also a defined way in the SEPA/EURO rulebooks and processing docs)
Of course nobody's using Wero now because the whole thing isn't really online yet, just a pilot program on a few websites with a few banks.