Some things that can be measured for estimating/following the success of enterprise architecture activities:

• Overall trends in enterprise, for which EA should correspond:
• Response time trend for business changes – EA has been successful, if the organization has become more agile.
• Efficiency trend for business operations – EA has been successful, if the organization has become more efficient.
• Reliability trend of business operations and development – EA has been successful, if the amount of failures (both in operation and development) has been reduced.
• Special measures for EA value:
• Maintenance of big-picture and reuse of EA information – the ratio of questions related to strategic decisions that can be answered, based on collected and maintained EA information, to the amount of questions that require a special one-time effort (study or project).
  
• Alignment of activities to business goals (the ratio of projects/solutions that are connected to the business goals, to the total number of  projects/solutions).
• The degree of standardization in business – the ratio of different "ways of working" to the overall number of business functions.
  
• The degree of standardization is IT – ratio of different used IT technologies to the overall number of IT systems.
• The degree of complexity in IT – ratio of supported business functions to the overall number of IT systems.
• The impression of stakeholders, how good/clear is the target ("TO-BE") picture – rating according to some subjective scale.
  
• The impression of stakeholders, how well complexity is handled – rating according to some subjective scale.
• Measures for strength of EA function:
• Strength of architecture governance – ratio of projects/solutions evaluated by architecture board, to the total number of  projects/solutions.
• Conformance to the architectural principles – ratio of projects/solutions following the architectural principles to the total number of projects/solutions.
• How well the architecture is followed – ratio of architectural exceptions to the projects/solutions evaluated by architecture board.