For delivering the customer expectations, it is essential that employees have the requisite skills to perform the job assigned to them as per the job description. Just theoretical knowledge is not enough. Employees need to have the skills to do their jobs, i.e. technical, analytical and people skills. this necessitates requisite training by trained and competent professionals. Training helps people to improve their competencies, and is necessary for doing still  better on the job in present and future.  Good training received also leads to better performance appraisal, which leads to employee satisfaction, and even engagement. A well trained person goes up high in his own esteem, and derives better job satisfaction from his work. Often, skills become obsolete also due to the emergence of new technology, which changes fast in some industries. So, employees need to update their skills to cope with the new challenges. trining helps in the requisite updation of skills.

The importance of training and development to organisations cannot be overemphasized. training and development empowers employees with requisite skills and abilities to deliver quality performance, especially when all other  things are equal. sometimes though training and development may not yield the desired results if its design did not consider transferability factors; i mean when trainnee cannot transfer training skills to the job they do.  

Training and development in organizations is very essential; they increase knowlege to the participants, improve skills, and can amend attitudes.

It is very essential for the following reasons:

1. Help in addressing employee weaknesses

2. Improvement in workers performance

3. Consistency in duty performance

4. Ensuring worker satisfaction

5. Increased productivity

6. Improved quality of services and products

7. Reduced cost

8. Reduction in supervision

http://www.artofthestart.com/importance-of-training/

http://www.insideindianabusiness.com/contributors.asp?id=923

I think you are asking about training program results.  Do they deliver?  There are several articles such as this one: Employee post-training behaviour and performance: evaluating the results of the training process by Diamantidis, Anastasios D. &

Chatzoglou, Prodromos D. in the International Journal of Training & Development. Sep2014, Vol. 18 Issue 3, p149-170. 22p.  They found that the design of the training program had the strongest impact on resulting job performance. In general, I would say that a training and development program must have specific objectives (are you trying to improve customer service? increase teamwork? have better quality?) and then measure results for those objectives prior to the training and then after the training to see if the training was, in fact, able to help the organization achieve results.

If the training is well designed, and participants are chosen wisely, and then given support, then results can be achieved.  There is also some evidence that training and development programs are being used as a recruiting tool. If someone knows that they will be given opportunities to develop their skills, it makes that employer more attractive to the potential applicant.  This would make it part of a "talent management" strategy.

Training and development programs should be not viewed only as a production performance matter. Training and development program are also a base to build new knowledge and skills for innovation. Those programs should be considered as a way to consolidate the capacity of an organisation to build what is call an “absorptive capacity” (Cohen & Levinthal, 1989, 1990, 1994). Organisations need to interact early with their outside and often turbulent environment. Development of knowledge and skills to identify weak signals in environment will give an organisation tools to innovate, a challenge of every day. Better performance in innovation will be a feedback as both creativity and CPS.

Some ref.

Cohen, W. M., & Levinthal, D. A. (1990). Absorptive capacity: a new perspective on learning and innovation. Administrative science quarterly, 128-152.

Lane, P. J., Salk, J. E., & Lyles, M. A. (2001). Absorptive capacity, learning, and performance in international joint ventures. Strategic management journal, 22(12), 1139-1161.

Puccio, G. J., Firestien, R. L., Coyle, C., & Masucci, C. (2006). A review of the effectiveness of CPS training: A focus on workplace issues. Creativity and Innovation Management, 15(1), 19-33.

Positive attitude and behavior of employees are essential for better performance of the organization. Training and development is essential tool for behavior modification. T&D is essential and important for developing positive attitude and behavior among employees.

Orientation process can be considered as a type of training and development. It is essential to all new employees.

Literature on transfer of training or training effectiveness might be insightful. Here some references that I found very useful.

In 1989, Baldwin and Ford after reviewing a large body of research in training effectiveness, developed a training transfer model that has had a stong impact on this research area. According to that model, transfer of training (application of new knowledge one back to work) is a complex process depending mainly on three inputs: (I) training contexts; (II) environmental context and (III) personal characteristics. Further, the authors distinguished training outputs from transfer conditions. The former are represented by learning and retention, which respectively consist of what people have acquired and retained as a consequence of participating in a training activity, while transfer conditions are represented by the processes of generalization and maintenance of new acquisitions ones back to work. Among inputs, outputs and transfer conditions, they highlighted a set of direct and indirect relationships that afterwards have been empirical tested (Alvarez et al., 2004; Burke and Hutchinson, 2007; Cheng and Ho, 2001; Salas and Cannon-Bowers, 2001; Tannenbaum and Yulk, 1992 are all literature reviews in which major results are reported). The meta-analysis that I have suggested cast some light on the relationship that have been suppost to be between inputs and outputs.

Aguinis and Kraiger, in their article, presented a "list" of benefits for the organization and society after reviewing qualitatively some of the most important studies of training effectiveness.

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