To protect the unions? It would be nice if life were really so simple, but face it - it's not! I've lived in the Seattle area most of my life, and even though our economy is more diversified than it used to be, it's still heavily dependent on Boeing. At one time, the entire economy of the area rose and fell with Boeing, now it's held a little more steady with companies like Amazon and Microsoft, however Boeing is still a major employer here. When layoffs happen or jobs move to other states, we still feel it in all parts of the local economy - unemployed people don't buy as much fast food, they don't buy as many electronic products, they don't pay for private music lessons for their kids, they don't buy musical instruments for their kids, they don't buy new cars, they put off normal maintenance on the cars they have, they don't visit the ski areas, and they don't pay for their kids to go to university. So, most sectors of the economy start to suffer, and tax revenue falls drastically. Sometimes a bit of an investment in the form of tax breaks serves to keep the economy strong and pays off hugely over the longer term as local jobs are protected.
Technically, I'm against tax breaks for businesses, but only because I'm against taxes for businesses, both large and small. Businesses large and small are job creators, without them none of us have an income, and yet our governments treat them as a revenue source, taking money that could be used to create more jobs. As a result, we have high unemployment rates and small businesses shutting down because the tax burden has become too heavy, and big business trying to make due with fewer employees than they should, raising employee stress levels far beyond what's healthy. As much as I don't like paying taxes, I think it would be far better to raise personal taxes and reduce or eliminate business taxes, to encourage job creation.
Oh yeah, and Tesla. Now I'm not off-topic. :)