If a person thinks that someone will not return his salaam, should he still say salaam?

Dear Brothers & Sisters,
As-Salaamu-Alaikum wa Rahmatullahi wa Barakatuh. (May Allah's Peace, Mercy and Blessings be upon all of you)
One of our brothers/sisters has asked this question:
If a person thinks that if he greets someone, that person will most likely not return his salaam, should he still say salaam or not?
(There may be some grammatical and spelling errors in the above statement. The forum does not change anything from questions, comments and statements received from our readers for circulation in confidentiality.)
Check below answers in case you are looking for other related questions:
Responding to a kaafir when he says salaam to a Muslim
Adding the word “ta’aala” to the greeting of salaam

Answer:

Praise be to Allaah.

Yes, he should still say salaam.

Whatever written of Truth and benefit is only due to Allah's Assistance and Guidance, and whatever of error is of me. Allah Alone Knows Best and He is the Only Source of Strength.
Your brother and well wisher in Islam

Related Answers:
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Ruling on initiating the salaam when speaking on the telephone
Responding to a kaafir when he says salaam to a Muslim
Adding the word “ta’aala” to the greeting of salaam

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