Undesired Angles with transform.Rotate(...)

I'm rotating a GameObject arround Y axis by 90º, "transform.Rotate(0, 90, 0);", and I'm getting a problem...the final that I'm getting is 90.00001º which can influence everything, if I translate the GameObject the position will suffer some undesired values too, very small but crucial values, can someone explain what am I doing wrong? I'm getting this in Unity 5.4.2f1 and 5.6.0f3

 transform.Rotate(0, 90, 0);