Measuring Agility of Agile methodologies: Agility Index Measurements
Although flexible methodologies can be seen as a means to an end, a number of approaches have been developed to quantify them.
The Agility Index Measurements (AIM) evaluates projects according to a group of factors.
The feature with a similar name - Agility Measurement Index , measures the development process against five dimensions of a software project: duration, level of risk, innovation, effort and interactivity.
Other approaches are based on measurable goals.
Developments based on fuzzy sets and fuzzy logic propose to use the speed of a project as a measure to assess the degree of flexibility of a project.
There are approaches for a team's self-assessment of whether and to what extent it uses flexible methodologies (Nokia test, Karlskrona test,  42 points test ).
Despite the evaluation attempts described above, their practical application remains to be assessed. Additional data can be found on the CSIAC ROI Dashboard.
Experience and acceptance
One of the earliest studies proving higher profits and improvements in business productivity using flexible methods was conducted by Shine Technologies from November 2002 to January 2003.  A similar study conducted in 2006 by Scott Ambler, who teaches Flexible Methodologies at IBM Rational's Methods Group, reported the same benefits. Others argue that flexible development methods are still too underdeveloped to require a broad academic analysis of their success.
Large-scale Agile development in the software industry continues to be an active area of research.
Flexible methodologies are also widely seen as more appropriate for certain types of environments, including small teams of experts.  : 157
There has been a positive attitude towards them in Europe in the field of embedded systems in recent years. 
Some of the things that can negatively affect the success of a project are:
Efforts in large-scale development (> 20 developers), although there are descriptions of scaling strategies  and evidence of applicability to some large-scale projects .
Distributed development activities (geographically divided teams. Strategies are described in "Bridging the Distance"  and "Using an Agile Software Process with Offshore Development" .
Forced incorporation of flexible methods in the team. 
Critical systems when failure is not an option (eg air traffic control software).
The early successes, challenges, and limitations of adopting flexible methods in a large organization are documented.
Regarding the "outsourcing methodology", Michael Hackett, senior vice president of LogiGear Corporation, states - "offshore teams ... must have the experience, good communication skills, intercultural understanding, trust and understanding between groups and among their members." 
Flexible methods are widely used for software development and some of them use certain software features (such as object technologies.  However, these techniques can be applied to the development of non-software products, such as computers, motorcycles). vehicles, medical devices, food, clothing, etc.
Risk analysis can also be used to choose between agile or value-driven and plan-driven methods.  Barry Boehm and Richard Turner argue that each part of the spectrum has its "territory" and applicability.
Critiques of Agile Methodologies
Agile methodologies may be ineffective in large organizations and in some types of projects (see section "Applicability"). They are best used for evolving and inconsistent projects. Many organizations believe that flexible methodologies are too extreme and adopt a hybrid option that mixes elements of flexible and planning approaches.
Agile has also been criticized by many observers as a whim of management, a term used to describe a change in philosophy or operations performed by an enterprise or institution. This term is subjective and tends to be used in a negative sense, as it means that this change is applied only because it is "modern" in management circles at the time, and not necessarily because of some real need for organizational change. Experience has shown that once the basic philosophy is no longer "popular", it will be replaced by the latest "popular" ideas, in the same way as the previous idea.