flowchart LR
    A["Ad hoc testing<br/>no standards or documentation<br/>quality is unpredictable"] --"5-level maturity<br/>systematic improvement"--> B["Standardize, measure,<br/>and optimize the test process"] --"Detect defects early<br/>reduce cost of quality"--> C["Achieve<br/>reliable SW quality"]

    style A fill:#FFEBEE,stroke:#D32F2F,color:#000
    style B fill:#E3F2FD,stroke:#1976D2,color:#000
    style C fill:#E8F5E9,stroke:#388E3C,color:#000
  

    flowchart LR
    L1["Level 1<br/>Initial<br/>Ad hoc & chaotic<br/>success depends on individuals"]
    L2["Level 2<br/>Managed<br/>Test policy & planning<br/>project-level management"]
    L3["Level 3<br/>Defined<br/>Organization-standard<br/>test process established"]
    L4["Level 4<br/>Measured<br/>Quantitative measurement & control<br/>predictable quality"]
    L5["Level 5<br/>Optimizing<br/>Continuous process improvement<br/>innovative test techniques"]

    L1 --> L2 --> L3 --> L4 --> L5

    style L1 fill:#f5f5f5,stroke:#ccc,color:#555
    style L2 fill:#FFF3E0,stroke:#F57C00,color:#000
    style L3 fill:#E3F2FD,stroke:#1976D2,color:#000
    style L4 fill:#F3E5F5,stroke:#7B1FA2,color:#000
    style L5 fill:#1E3A5F,stroke:#1E3A5F,color:#fff
  

    flowchart TD
    subgraph R1["​"]
        direction LR
        A1["Assessment<br/>Diagnose the current test<br/>process level based on TMMi<br/>gap analysis, derive improvement tasks"]
        A2["Set target level<br/>Reflect organizational strategy<br/>staged PA achievement targets<br/>determine priorities"]
    end
    subgraph R2["​"]
        direction LR
        A3["Execute improvement<br/>Define processes per PA<br/>build tools & templates<br/>run a pilot"]
        A4["Measure & verify<br/>Track test KPIs<br/>verify improvement effect<br/>certify level-up"]
    end

    style A1 fill:#E3F2FD,stroke:#1976D2,color:#000
    style A2 fill:#F3E5F5,stroke:#7B1FA2,color:#000
    style A3 fill:#FFF3E0,stroke:#F57C00,color:#000
    style A4 fill:#E8F5E9,stroke:#388E3C,color:#000
    style R1 fill:none,stroke:none
    style R2 fill:none,stroke:none