@Override
    public <T> IClientConfig set(IClientConfigKey<T> key, T value) {
        Preconditions.checkArgument(key != null, "key cannot be null");

        value = resolveValueToType(key, value);
        if (isDynamic) {
            internalProperties.put(key, Optional.ofNullable(resolveFromPropertyResolver(key).orElse(value)));
            autoRefreshFromPropertyResolver(key);
        } else {
            internalProperties.put(key, Optional.ofNullable(value));
        }
        cachedToString = null;

        return this;
    }
Store the default value for key while giving precedence to default values in the property resolver
ribbon-core/src/main/java/com/netflix/client/config/ReloadableClientConfig.java