I think two things are being confused in this discussion - depreciation and (179) deductions. They are not same. The differences will likely strain the interests of us trying to get product out the door and orders in….but the OP asked for understanding I think its an important distinction toward that
First thing is, there are really two sets of books a company keeps, financial accounting and tax accounting. Financial accounting focuses on properly representing the business in its financial statements whereas tax accounting is figuring out your corporate tax return. Depreciation is the using up of the asset over time in financial accounting, deductions shelter income on your tax return.
Why are they different? Financial accounting, trying to represent the business, says that the machine bought will show up as an asset on the balance sheet. Gradually over its life that asset value is reduced, and the amount it is reduced by each year is expensed (reduces profit) for that year – that is depreciation. This reflects reality, the machine is used up over say 10 years, so it should be profits over that same period of time that are reduced, as its used up. Financial accounting is regulated through GAAP for you guys, and IFSR for us and the rest of the world (we were GAAP but switched a few years ago to IFSR, they’re not that different at this level). If you understand it, it does a very good job of representing business reality in a few pages of numbers
Tax accounting otoh and the 179 deduction are different. Tax law is 100% driven from fiscal policy. The guv wants to encourage say more capital investment so they let you deduct from income (so you’re not taxed on it) as much as you can as soon as you can. The deduction accelerates the tax savings you get over depreciation. Would you rather shelter 90Mof income next year, or 9M per year for 10 years? Assuming rates were the same, you’re better reducing the tax paid today and putting it to work today.
Why does it matter?
Reality is better represented by showing the asset on the balance sheet, and expensing it a bit each year. That may not matter to a one man show, but it does in a bigger business. If you’re a bit bigger and have a bank and/or shareholders or one day are valuing the business for sale, it matters a lot – in the scenario described above profit being reduced 9M per year for 10 years correctly represents things. If you were able to depreciate it all in one year (you can’t) you’d end up with wild swings in profit that aren’t really there (the wild swings ARE picked in the cash flow statement, so the accounting is not hiding anything, really its saying the profit should be reduced over the time period the asset is used up)
Clear as mud?