monopolyzing Products - Good/Bad?

What does Market Monopoly mean?

Monopoly is the market condition in which we have only one provider of a particular service. Such a situation is beneficial for service providers as they enjoy the freedom of lack of market competitors. The customer has no alternatives for the available service and has to buy the service at given facilities and cost.

https://www.buzzle.com/editorials/1-13-2005-64198.asp

Few examples are microsoft products only work on Microsoft OS, some games only work on specific consol's...quiet a few actually ...

Q1. Is monopolyzing one's product a good business stratergy?

Q2. Monopolyzing ethical?

Q3. Doesn't monopolyzing jeopradises healthy competitive market?

Q4. Whats the worst monopolyzed poduct you dislike and why?