This is the 6487th most frequent Japanese word.
ソク
"ソク" (soku) can mean "instant" or "prompt," depending on context.
In this sentence, 'ソク' is used to mean 'immediately,' referring to the immediacy in using the shoes without preparation.
この靴はソクで履けます。
These shoes can be worn immediately.
Here 'ソク' conveys immediacy or directness, describing the hindering factors as being directly impacting or relevant without delay.
その問題の解決にはソク邪魔する要因があります。
There are immediate hindering factors for solving that problem.
In this instance, 'ソク' signifies the quickness or promptness of providing a reply.