What causes Investment

Just finished reading Greenspan's Fraud by Ravi Batra.

Made me view investments in economy differently. In JC, the typical way to increase investments in the economy is simply to lower the corporate tax, and businesses, with the extra profits, can then increase investments. Supply will then increase, bringing a price decline and offsetting inflation. However, in the book, it is said that corporate tax cuts do not affect investments all that much, as in the face of declining sales, even a decline in corporate tax will not be incentive for companies to increase investments. In fact, the only incentive that allows companies to increase their investments is only when they face increasing sales.

This in turn made me think more on the Jobs Credit Scheme. JCS is meant to save jobs, but in the face of declining aggregate demand, why would companies still want to hire workers in the first place. Furthermore, JCS is more geared towards business companies, where it is equivalent to a corporate tax cut by putting more money in the hands of companies. If companies are unwilling to invest(employ more workers, create more products, etc.) because of the declining sales brought by the slump in aggregate demand, the JCS will not be effective in preventing job losses at all.