BPMN Legend of Common Errors PDF

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Common errors in BPM legends Common errors in BPM legends Common errors in BPM legends Common errors in BPM legends Common errors in BPM legends...

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BPMN Legend of Common Errors LEVEL 1 ACTIVITIES

① ② ③ ④ ⑤ ⑥ ⑦ ⑧ ⑨ ⑩ ⑪ ⑫ ⑬ ⑭ ⑮ ⑯ ⑰ ⑱

Bad activity name – should start with verb Activity without inflow Activity without outflow Missing activity Activity must be named after work done by the actor Activity must model work and take time Task should normally model a single and entire uninterrupted session of work Tasks too algorithmic – should all be modelled in a single task. Activity does nothing Data available is not sufficient to perform this activity GATEWAYS A Gateway should not model work Data for a decision gateway must already have been created or received upstream Decision gateway should named by a question or its branches by conditions Bad branch label – should be condition or value Missing label on data-based gateway branch Exclusive gateway conditions not mutually exclusive Missing branch or missing default Branch condition undefined

FLOW

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Sequence flows should not cross each other

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A None Start event should not be named

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Activity attributed to wrong actor

Generally flows should point left to right Plain Sequence Flow should not be named Incorrect use of merge – should be join (synchronization) Not clear where or if this parallel fork synchronizes Incorrect use of join – should be merge Merge combines concurrent threads, so subsequent activity performed twice Activities in wrong order These activities should be concurrent These activities should be sequential This condition is always FALSE Deadlock Missing branch and loop Bypassing synchronization from concurrent thread is potentially unsafe EVENTS (Start and End) End Events must be named by an assertion describing the process state A Terminate event is required only if there are active concurrent threads Externally initiated process should start with a Message Start Event Internally initiated process should start with a None Start Event A Catch Link Event must have only one corresponding Throw Link Event and vice versa. RESOURCES Resource allocation too coarse Organizational units generally not appropriate for naming roles Activity has not been allocated to a resource class Preferably allocate a subprocess to the initial actor POOL

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External participant must be modelled by black-box pool Black-box pool must not show activities Sequence flow must never cross a pool boundary Pool containing a child process should have the same name as the parent pool. White-box pool should be named after the process, not the participant.

SUBPROCESS

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Subprocess should have only one start event. Subprocess must start with a None event. Sequence flow must never cross a subprocess boundary Subprocess cannot be re-entered from a boundary event Subprocess does not have an expansion Missing condition label on subprocess End event Generally a subprocess should contain more than one activity. Task requires many sessions so should be modelled by a subprocess. Unnecessary and undesirable to merge threads immediately preceding an End Event. Unnecessary to show child message flows in the parent Terminate event in child process can never end its parent. MESSAGES

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Message flows should be named by the data object transmitted A gateway cannot receive or send a message Message flow not allowed within a pool At Level 1, message must attach to an activity or a pool Request has no matching response. MISC

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Inconsistent notation Inconsistent with narrative Notation not legal BPMN Undue or excessive use of BPMN annotation Undue or excessive use of BPMN data artefact Undue or excessive use of non-BPMN documentation Confusing or excessive use of links GLOBAL

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A process model must not contradict the process on the ground Model an end-to-end process in a single pool Significant features of the narrative have not been modelled....