Observing the correct installation of shower screens can easily prevent this kind of failure. Australian Standard 3740 1994 – Waterproofing of wet areas within residential buildings clearly sets out the location of screens in relation to hob construction.
Screen enclosures when fitted to hobs are required to be fitted flush with the inside vertical face of the hob and sealed at that location with flexible sealant.To enhance the efficiency of the mechanical sealing at this location, an angle over the inner vertical/horizontal junction of the hob can be incorporated. This will then act as an extension of the screen over the junction of the vertical and horizontal tiles.
For further information refer to the PDF below.