thank you Robert,
I took your advice and tried the following things.
Please find below, "First Test Queue" setting details.
・Queue/Routing/Routing methods：Standard ACD
・Queue/Routing/Evaluation Method：Disregard skills, next agent
・Queue/Members(users)：1 persons(userA)
・Queue/Direct/Backup Queue："Second Test Queue"
・Queue/Direct/Assign to backup immediately：On
・Architect/Transfer to ACD/Routing/Preferred Agents：No Value
・Architect/Transfer to ACD/Routing/Direct Agents：userA
Please find below, "Second Test Queue" setting details.
・Queue/Routing/Routing methods：Standard ACD
・Queue/Routing/Evaluation Method：Disregard skills, next agent
・Queue/Members(users)：2 persons(userB, userC)
・Queue/Direct/Backup Queue：Blank
・Architect/Transfer to ACD/Routing/Preferred Agents：No Value
・Architect/Transfer to ACD/Routing/Direct Agents：No Value
As a result of following steps
1. Set 1 people(userA) to "off Queue" & "available"
2. Set 2 people(userB, userC) to "on Queue"
3. A customer calls an agent.
4. "userA" alerting interaction is displayed, incoming called, press "BUSY"
result＞"userB"&"userC" alerting interaction is not displayed, no incoming calls.
I imagine that after "userA" press "BUSY", "userB"or"userC" incoming calls, but this is different.
I don't know much about "Direct Routing", so I will try to try this and that settings.
If think of something good, please let me know.
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Katsuya Yamasaki
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Original Message:
Sent: 11-11-2024 15:56
From: Robert Wakefield-Carl
Subject: There's some uncertainty regarding about Incoming queue running for which "Direct Routing" is set
The idea of direct routing is that use DID's can still be used without assigning them to a flow. The Direct Routing allows you to specify what numbers that are assigned to users should have special handling like a message about recording. Once you have it directed to a flow, here are examples of what you can do: Direct routing overview - Genesys Cloud Resource Center
From what you propose above, it seems like Preferred Agent might be considered over Direct Routing unless you use the backup settings for direct to get the queue for these other agents.
As for the queue setup, that is explained here: Set up direct routing - Genesys Cloud Resource Center
You setup routing to standard: 
Be sure to setup the Direct tab in the queue as well:
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Robert Wakefield-Carl
ttec Digital
Sr. Director - Innovation Architects
Robert.WC@ttecdigital.com
https://www.ttecDigital.com
https://RobertWC.Blogspot.com
Original Message:
Sent: 11-11-2024 04:40
From: Katsuya Yamasaki
Subject: There's some uncertainty regarding about Incoming queue running for which "Direct Routing" is set
Hello,All
I am currently using a translation service, so I do apologize for any grammatical, or translation errors.
Also, please forgive me if this isn't the correct place to ask this question.
Please find below, First Setting details.
・Queue/Routing methods：Standard ACD
・Queue/Members(users)：3 persons(userA, userB, userC)
・Architect/Routing/Preferred Agents：No Value
・Architect/Direct Agents：userA
As a result of following steps
1.Set 3 people(userA,userB,userC) to "On Queue"
2.A customer calls an agent.
3."userA" alerting interaction is displayed, incoming called, press "DECLINE" & "BUSY"
result＞"userB"&"userC" alerting interaction is not displayed, no incoming calls.
※"userB"&"userC" press QueueButton on and off, didn't change not displayed, no incoming calls.
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Please find below, Second Setting details.
・Queue/Routing methods：Preferred Agent Routing
Route to preferred agents with score greater than or equal to:score100
・Queue/Members(users)：3 persons(userA, userB, userC)
・Architect/Routing/Preferred Agents：MakeList(MakeAgentScorePair(FindUserById("userB"),100))
・Architect/Direct Agents：userA
#ArchitectureandDesign
#Routing(ACD/IVR)
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Katsuya Yamasaki
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