Shrubs slowly dying
Left photo - It looks like your cherry laurels are showing symptoms of cherry shot hole disease. Cherry shot hole is a foliar fungal disease favored by wet weather. The infected leaf tissue falls out and "shot holes" are left behind. The damage is cosmetic and no chemical controls are recommended.
Right photo - We notice cherry shot hole and some old chewing damage from insects. At this point, we recommend that you lightly prune back any dead branches and unhealthy foliage. Let the plant recover and put out new growth. Monitor the plants this growing season. Make sure mulch is no thicker than several inches and away from the base of the stems. Water during dry periods.
Here is our blog post for more information (possible disease and insect issues) and how to grow cherry laurel in your landscape.