One reason, By increasing your deductions and expenses it will decease your income and you may not be getting as many credits as before like the EIC credit. You can't go by the refund monitor until you have entered everything in. Also after you reduce your income to zero there is no more refund to get back.
Do you have more Itemized Deductions than the Standard Deduction? That's not common since the Standard Deduction was increased.
For 2019 the standard deduction on 1040 line 9 amounts are:
Single 12,200 + 1,650 for 65 and over or blind
HOH 18,350 + 1,650 for 65 and over or blind
Joint 24,400+ 1,300 for each 65 and over or blind
Married filing Separate 12,200 + 1,300 for 65 and over or blind
