The problem is that all you see is a number, not an estimation of the satoshi/byte that you'll be sending. Since Blockchain's ordinary fee estimation is either 120 satoshi/byte (wayyy too low) or completely unpredictable, you just end up having no idea what kind of fees you're sending at all.
That and even if you set high fees,it will throw an error stating "The fees you have chosen is higher than the usual you may want to lower it" but their estimation isn't right.Better use a fee calculator and send the transaction with estimated fee anyway.