Fiscal responsibility isn't a 'left or right' issue. It's a matter of how you look at economies and money. There are times where a government shouldspend more money than it's gaining through taxes, and times it shouldn't. But the most important concerns for a government are 'is this going to pay for itself in extra taxes over the next 20 years, maintenance etc. included' and 'if it doesn't, how much will our future citizens end up coughing up to cover the shortfall.'
A lot of governments, and not just left wing, right wing, centrist or otherwise governments, are really bad at making that estimate. Or rather, they ignore whatever naysayers there are (including those that they hire to tell them whether or not the numbers work out) and just do what they want because it means they get reelected. Trading an ever increasing (by percent GDP) loan burden (and thus also tax burden) for power, until it matters no longer and the economy collapses because either the government stops paying people (because it can't borrow more money) or because of runaway inflation (because by printing more money without actual economic activity to back it up means less valuable money). It's just something of a future problem, especially if an economy is well diversified and thus hardened against price shifts in a single or small group of related commodities.
When that isn't true, well... just ask Venezuela.
A lot of governments, and not just left wing, right wing, centrist or otherwise governments, are really bad at making that estimate. Or rather, they ignore whatever naysayers there are (including those that they hire to tell them whether or not the numbers work out) and just do what they want because it means they get reelected. Trading an ever increasing (by percent GDP) loan burden (and thus also tax burden) for power, until it matters no longer and the economy collapses because either the government stops paying people (because it can't borrow more money) or because of runaway inflation (because by printing more money without actual economic activity to back it up means less valuable money). It's just something of a future problem, especially if an economy is well diversified and thus hardened against price shifts in a single or small group of related commodities.
When that isn't true, well... just ask Venezuela.