yarn错误The engine "node" is incompatible with this module

今天在用yarn安装vue-cli时出现了错误
../vue-hackernews-2.0> yarn
yarn install v1.12.3
[1/5] Validating package.json...
[2/5] Resolving packages...
[3/5] Fetching packages...
info fsevents@1.1.3: The platform "win32" is incompatible with this module.
info "fsevents@1.1.3" is an optional dependency and failed compatibility check. Excluding it from installation.
error upath@1.0.4: The engine "node" is incompatible with this module. Expected version ">=4 <=9". Got "10.14.2"
error Found incompatible module
info Visit https://yarnpkg.com/en/docs/cli/install for documentation about this command.

进行这个设置之后，会正常。 

yarn config set ignore-engines true

但是这是什么原因那？

解析如下：

我的node.js安装包是8.2版本的，支持vue-cli 3.0版本以上需要v8.9以上