There is no general guideline for this.
This depends on how experienced/good the devs are, how new the technology is they might be using, how complex or new the application is they are building, etc.
For example if it's a long ongoing project were only small changes are done, you should find next to no bugs, however in a new project that is just being started you might have a failure rate of 50% or more.
The only number that could be decided on upfront is how many % of the test cases you need passed/successful before testing can give their "GO", which is generally an agreement that is made with the customer/business/whoever is paying or responsible for the project.