If you are a strict boss, your sub-ordinates work best when you are there. But if you are a friendly boss your sub-ordinates try to do their

Sir, the first one can be true when the boss is strict , uncaring and who doesn't value his employees, and when employees lost motivation to work for the boss.. 

If the boss is friendly, cares for employess and shares the common goals, and one who is transperant in decision making always have his team's backup.. Once team understand the deadlines, they work hard towards it to make it happen no matter their boss is around or not..

I totally disagree with you on this.

It has nothing to do with strict or friendly manager.It has to do with HONESTY (أمانة).

I may say that where there is a friendly manager, employees may make use of it and pretend to work hard if he is arround, while they don´t. Even when he is not there, they don´t.

I don´t want to give excuses to those who don´t take the responsibility to doing their job well.

It is employee's honesty that detrmines the difference between their effort whether their manager is arround or not.

No, I find it difficult to agree with such classification of boss. If this is the case (that when the boss is around, employees work hard and vice-versa in his absence) then the boss is the one and only person to be blamed for not being able to motivate the employees. 

I don't think so. coming to the first point If boss is strict he can get normal work from his sub-ordinates may not be the best from them. For the next, being friendly alone can not produce best results. it depends on the Jr. Colleagues (preferred word than sub-ordinates) motivation level and attitude. Moreover, Jr. Colleagues should have faith and confidence with the boss which makes them to produce best results even if his boss is not around there. Finally, Jr. colleagues should always feel that they can put hand on his boss's shoulder any time but they should dare to do it. 

i would say "accommodating nature" brings the integrity in the team. It does not have to do anything with the temprament or nature. If an employee is capable enough to understand his/her duty, performance would be the criteria.