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Often a high number of merges is an indicator of trying to model “too much functionality” with a single model. In these cases, other symptoms commonly include a high model complexity (see section Model Complexity) as well as use of state variables (see section Avoid Overuse of State Variables). Here, the good intentions of reuse backfire into unnecessary model complexity: (multiple) state variables are deployed to “remember” which (combination) control flow branches have “taken” prior to the merge(s) which quickly increases risk for modeling error as well as diagram complexity, and reduces understandability. In these cases generally the best option is to split the model into multiple models and reduce this way the merges required.
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