"The highest way is to be held in love and care which amount to respect "

Love is much more irrational and its make people do (sometimes) stupid things. like, going sacrificing all they have for a project just because they love the leader and or the feeling of accomplishment,so they do it anyway. They are maybe inspired by the future glory,which is much more motivating than the limiting fear .

So it can be deduced than using fear indeed gets the job done but its a short term solution. Once the job is done you have no loyalty. Having both fear and love is better options,but you can you really be both?

So much mystique and aura around one quote.

This quote has gone from the perspective of political science ,government and military science to leadership in business. The mystique and aura around it are primarily from people who haven't read Machiavelli's The Prince. While some people don't even know the full quote. "It is Better to be feared than loved if you cannot be both."

What does this mean?

In his book, Machiavelli states that love is internally based. Its a feeling you choose to have, one that can turn you on and off easily. Fear is much more predictable and largely externally based. Lovers can fall out easily but fear does not wear off if the cause character remains.
But note that "if you cannot be both" part of the quote.
The highest way is to be held in love and fear which amount to respect.

Fear and love seem to be key in leadership. If you can get people to fear you, you can get tons of "productive" work done. But if people fear you (or the project/mission),you are only leveraging on a source of motivation .people's fear.

Perhaps choosing to start with fear, then love,is better.

This is the method good coaches apply,they're tough initially and once they get your head in the game they respect you and you return that respect .it's a relationship .Using fear alone will win some games but then people look elsewhere for respect .