What is the key to have a successful business?

In my view any business can be successful if you can satisfiy and make comfirtable as much as you can to your customer and 2nd thing is to determine / agreed the reasonable T & C before the conmencement of any project. 

1. Reliability
2. competence
3. openness
4. compassion
5. Team Work

the good wise management , good team work

Smartness, conscientiousness and perseverance 

Most importantly punctuality , dedication , hard work   

Hard work, dedication and timely delivery of project.