OnInitializedAsync() in blazor

I have used OnInitializedAsync() in my code. In that hook, I am fetching data.In markup, I have checked whether data is null or not. But I found that data checked is executed before the onInitalizedAsync() triggered. Meanwhile, after getting data too, data checked is executed.

I have checked the blazor documents but struggling to find why it triggered at first.

<Component1>  @if (Data != null)      {        @foreach (var item in Data) {<Component2>        }       }</Componet1>@code{  protected override async Task OnInitializedAsync() {       Data = //data from dataBase  }}

I need to execute data checked only after data fetch. Can anyone guide me to fix this issue?