Then don't buy.
Mining income is based on bitcoin price and on how many bitcoins are created in each block. That's all.
If people can gain from mining they will jump on it and difficulty will rise until no more people jump on it
But then what is the incentive for me to spend money mining bitcoins? I'm not trying to be difficult or an "ass" I just want to understand the whole process.
Right now there is a soon to come tech transition period. Those that have invested in old technology with an inability to move forward with ASIC purchase will most definitely lose.
On the bright side, ASIC represents the most purpose specific technology for performing the calculation that ultimately earns a subsidy from the Bitcoin protocol. So, yes, don't spend your money on any older technology. Wait for the ASIC if you are going to get involved in mining.
Addressing profitability directly. The Bitcoin protocol allows for a currency injection period until a max of 21 million bitcoins are generated. The Bitcoin mining process is responsible for this currency injection (among other things). To incentivize the activity of mining, which carries a capital and operational cost for the miner, the currency injection is rewarded to the miners. This is where the profit lies. How much profit you can make is entirely dependent on how much mining hash power you can bring to the table vs. the total hashing capacity of all miners. If there are too many miners hashing revenue aka the currency injection will be more distributed requiring any one single miner to invest more capital in hashing power to gain more revenue. There is a point where reward revenue per your hashing capacity is not sufficient to surpass capital and operating expenses.