Wales top scientific adviser says he "very much hopes" there will be no further lockdowns.
Dr Rob Orford also said that the advice on further coronavirus restrictions in December was not an over-reaction.
The scientist, who is co-chair of Wales' expert Technical Advisory Group (TAG) and represents Wales on the UK's Sage committee, told BBC Wales that the "retrospect-oscope" is a "really powerful instrument."
In the middle of December, the Welsh Government was given strong advice about introducing a stringent post-Christmas lockdown in Wales as Omicron was detected and cases started to rise.
Scientists told ministers that four weeks of strict restrictions would have the biggest impact on holding back the number of cases. Read more here.
"We will go back through a public inquiry to look at all these decisions and ask what was the underpinning evidence, what was the confidence in the advice," he said.
"During that period on 15 December the advice we brought together for ministers had a high degree of uncertainty about whether this (Omicron) was less severe or more severe than Delta - because quite simply we didn't know.
"So in that modelling we expect the best and prepare for the worst."
When Dr Orford was asked about learning to live with coronavirus, he said: "I wouldn't say I'm confident, I'd say I'm cautiously optimistic."
He did warn that protections such as self-isolating and working from home might be needed for some time to come, but he hoped high levels of vaccination meant Wales could start to learn to live with the virus.
Last week, Wales' top medic has said that there is "room for cautious optimism" that the endemic is in sight as cases from the Omicron start to fall and hospitalisations decrease.
Dr Frank Atherton has said it is still too early to say but a good outcome would be that the country moves from pandemic to endemic, where coronavirus becomes seasonal like flu. Read more here.
He added that more than 90% of people in Wales now have some level of immunity against coronavirus.
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